Ok, so some friends and I went to a junk yard a bit ago and I scored a brake and clutch pedal/bracket set out of a 90ish toyota camery. I tackled the brake first. ended up pulling the ls400 brake pedal and bracket mount out entirely and looking over the both of them. they ended up being only slightly different, but no way was the camery pedal bracket mount going to fit in there so I decided to just swap the camery pedal into the ls400 bracket mount. the hinge width, and distance to master cylinder hole was exactly the same. The only thing is that the camery had a slightly smaller through hole for the interface with the master cylinder and the switch pad was on the oposite side of the pedal. so first thing I did was pull out a letterd/numberd drill set and drilled out the hole to the correct size for the ls400 master cylinder pin. I believe it was size O.
Then on to the brake switch pad. First I cut off the switch pad from the ls400 brake pedal. Placed the pedal in the bracket and lined everything up and buzzed it on with the mig welder.
After that it was just a simple re-install of the camery pedal in the ls400 mounting bracket back into the car. hooked everything back up and whala.
All set. Dono if i am super happy with the distance of the brake pedal to the gas seems it may be hard to do heel toe braking maneuvers with it in this orientation, but if so I can easily cut and re-weld the pedal arm itself to suit my needs. For now though its fine. On to tackle the clutch.