New garage door opener installed.Chamberlain, B503, June 8, 2019 (8 Pics)

I cannot begin to voice my displeasure with the poor writing and the apparent lack of any editing in the instructions. Anyway, aside from a game of "guess the wire placement," it was a pretty straightforward build. The problems arose from the individual garage and were nothing that anyone attempting this sort of thing couldn't devise a fix for.

The adjustments on the unit were a pleasure compared to the old "adjust the stop on the screw drive" type. To lower the unit, push down until the door is closed, then push down again. Set. Push up until the door is in the up position, then push up again. All done.

It was a twelve hour job for me, partially from having to stop and figure out solutions to mounting problems.

The gear was mostly chewed down from age, the chain wouldn't stay on any longer.

Pics of the original wiring.

My solution to the new length of guide arm. The drive fell in between the roof joists, so I used the steel brackets to bridge the gap.

Stubborn Determination.

Installed and operational!