Not a problem. I was an early beta tester for the Dynon Autopilot and it works well with the D100.
Here are some pictures of the installation. You will want the AP74 as it really improves the AP interface. No need to make the bracket I describe on my web site as that is now standard.
The pitch bracket should be riveted to the belly skin but if you or your local A&P can't / won't rivet it to the belly, a number of people have simply used AN3 bolts to secure it to the rib and leave the bottom rivets off.
The roll servo is very easy to install, no issues there.
The biggest pain is removing the interior to run the wires.
After you install it, you will want to upgrade the software, which you can download from Dynon's web site. Knowing Dynon continues to improve their products with software releases, you might want to mount a DB9 connector in a convenient location, if that has not already been done.
Here is a picture how I mounted the DB9 connectors for my D100 EFIS and D10 EMS. By updating the Dynon EFIS with all the auto pilot parts powered up, their program will update the servos, AP74, and EFIS all at the same time. You will have to update the Dynon EMS separately but at the same time, if one is installed.