I just completed this swap the other day and it went fairly well! Biggest challenge was selecting the two (smaller) red red/black stripe wires and pulling them back....they were stuck to the other wires..... but the WD 40 thing in the sheathing worked....put a small hole in the sheathing at the top where it enters the car, and sprayed it in both directions.....eventually after pulling with a "smooth" needle nose, no teeth! The wires popped loose and pulled easily while lubed up!
Just a note, in the drawing for the switch bracket, the smaller hole was referenced for a letter drill "O" which many won't have access to, but a 21/64" drill bit from my cheapo Harbor Freight drill selection had one that worked great! Slipped right over the stud!
One last note is that if you needed to have your switch just a little further from the brake pedal arm, you can leave the nut on the rubber stop shaft and the slip the new bracket in place and then add a new nut on top.... I found one off of perhaps an old ball joint bolt for the Mangusta......that went on.....but in the end, I didn't need to do that. Just throwing this out there.
To those that wonder, you do not need to disturb the adjustment for the pedal stop at all doing this job. No need to. The nut, once loosened should spin right off, put your new bracket in place (I added a thin lock nut) and spin the nut back down....done!
Cheers!
Steve