Please note that this guide is applicable for my car and even if your car is a MY13 model it can have differences in the wire harnesses. Perform any modifications on your own risk.
First thing is to get the Electrical Wire Diagrams for your car. You can do that from here – http://vidaresources.volvocars.biz/ewd/Eng/index.html
Using the EWD for the car you can see how is your car wired now and how the wires have to go for the Xenon lights to work properly.
My car came from the US market and had the Headlight washers in the front bumper and regular Halogen headlights. 
Next requirement for the ABL to work is the car to have gyroscopes on the front and rear axles. Both were mounted on the right side of the car and only 1 is enough per axle.
I purchased a set from a crashed XC70 from 2008 and asked the seller to send them with the connectors still on them. 
Removed the rust and painted them black.
Next I started with the Rear End gyroscope. I ended removing the rear seat bottom part to locate the cable harness connector between the rear axle harness and the main floor harness of the car.
To my surprise the connector already had the wires I needed, which meant that the car had wires already from the rear end gyroscope to the CEM.
Removing the rear right wheel confirmed that as the cable end was clipped on a plastic placeholder.
After removing the plastic I was able to install the new gyroscope.
The gyroscope is secured with 3 nuts to the chassis and to the suspension.
Next is the front gyroscope. Removed the wheel, the under fender plastic, secured the gyro to the chassis. As the car was not produced to have Xenon lights from the factory, it was missing a thread to fix the lower part of the gyro to the suspension.
I cut a new thread inside the marked hole and used a normal bolt to secure it. Used some cable ties to secure the wires under the fender. 
I routed the 3 cables from the front gyroscope behind the right headlight and following the factory harness around the coolant expansion tank and going in to the firewall.
There is a sealed communication hole next to where the harness is going in the firewall. I had to cut it and route the cables. This hole is also used for the new wires coming from the right ABL headlight.
Then I removed the CEM module. It is located under the glove box. Disconnect all 5 connectors from the CEM, and any other cable that is in the way. The CEM is twisted to one side to get out of the metal clips that are holding it. 
Once the CEM was out of the way, I opened the right side of the plastic under the windshield wipers. It is hold be few clips. That way I was able to route the cable in the hole I have cut in the firewall in the middle space before the inside of the passenger compartment. I used a screwdriver to punch the isolation until I saw it on the other side and pulled all the cables to the other side. 
I used Volvo original repair terminal cables to connect the gyro to the CEM connector. In the case of my car (XC70 MY13 NA Market) I had to connect the 3 cables to the Connector 1 of the CEM (Green one) in places C1:35/36/53.
To be able to connect the wires, I opened the cover of the connector using a small flat head screwdriver. The cover is designed to be taken off easily. The flat head is used in each corner of the connector to push the cover corners out of the clips.
Each slot is numbered on the connector and you can see where to put the cables. The repair terminals used for all connections to the CEM are 30656698 (Cable Repairkit Blade terminal sleeve Type C Tin). 
Once the Gyros were done I moved to the wiring of the headlights. Both headlights are the same.
I prepared the needed cables before hand. I was lucky that the seller of the new ABL Headlights send me also one of the connectors from the main harness. I managed to salvage the needed pins from it.
I had to make several changes to the existing wires. Two of them were made redundant as they were connected to the wrong modules on their other side.
I made the following changes to the Headlight plugs.
POWER to the ballast of the XENON
Pin 4 in the Connector had to be linked to the cable on Pin 10. This is the Ground connection, so I directly connected Pin 4 to the proper Grounding point next to the headlight.
Pin 5 in the Connector had to be linked to the cable on Pin 9. I cut the insulation of the cable connected to Pin 9 and soldered the cable from Pin 5.
Those two are the + and – for the ballast that powers up the Xenon
CONTROL and GROUND of the ABL motors
Pin 8 in the Connector had to go to CEM. This is the control signal for the ABL motors. Left Headlight goes to C1:19 on the CEM. Right Headlight goes to C1:20 on the CEM.
Pin 12 in the Connector had to go to Ground. In my case it was going to the Light Switch Module, for the manual adjustment of the level of the headlights.
The cables from the Left Headlight were routed around the battery box and under the windshield wipers.
After all the cables were connected, and everything was put back in to it’s place, I used VDASH to change the CEM configuration from Halogen Headlight to ABL Menu Controlled Headlights.
Then VIDA was used to make first calibration of the Gyroscopes.
The end result.
And a video of the end result.
Some conclusion.
It was really strange that the NA cars have the needed cables in the rear for the Gyroscope, the headlight washers and the Headlight switch without a turn knob for leveling, but Volvo has decided to not put 3 wires for the front Gyroscope and 2 more for control of the ABL motors. Seems to be a strange way of cutting cost on the front wire harness – 5 wires, while the rear harness is a separate part from the main floor harness but still has the extra wires.
I have intentionally not give exact instructions on the Connections, as different models and different years have different wiring, so the best way is to read the link in the start of the port and see how to connect the wires on your car in the EWD.
This is not as easy DIY, but the difference from Halogen to ABL BI-Xenon is huge.
I hope this helps some one to make to conversion.