I reached out to Paul, the engineer who designed and builds the ARP.
Here is his e-mail back to me:
One must remember that when a manual is written for a universal product, there is a lot of info.
Most of the info is not needed, rather focus on the Make and Model of fridge you are installing for.
Call Paul if you have any questions, he is there to help.
The drawings for wiring are straight forward, in addition there are videos for the installation of the boiler sensor.
Like anything else, small steps make it manageable, and the links in the manuals are cross references for your convince.
Only follow the links if you need further information.
Basic wiring video: https://www.arprv.com/installation-procedures.php