They mount at 17 degrees. I made a custom shim plate to strengthen where it mounted and to tilt it. The conversion had the firewall vertical, stock was angled downwards slightly.
Return springs were not used, but if it helps, all good. The brake light switch works in such a way that it can be in the wrong location, or custom and still work the same. Basically, they are self-adjusting. You pull the brake pedal back as far as it will go towards the seat. That is also pushing the switch button in and moving the body if needed too when it bottoms out. From there any time the pedal goes forward, it also activates the lights as button released. Perhaps the pedal was hanging a little, bouncing the button, hence the spring. Whatever works. I realise you likely know all this!
Bill, you mentioned elsewhere that it has a new rubber rear hose as the braided didn't fit. Unrelated but do you recall what was wrong with the braided, or brand etc? I had one years ago, found it didn't fit, wrong length I think, can't recall. I then picked up a replacement, lost it. Ordered another, lost it. Did the brakes, forgot I hadn't done the rear hose, found them all later. I think I have a few variations there, was wondering if yours was the same as any.