35 for a TM spring guide is also laying it to you. 55 for a metal one is horrible. I've got my systema bearing spring guides for 25ish.
You say he did your wiring for free...given he managed to break a spring guide on an initial install, charge you WAY too much for a TM stock piece and rip you a completely new hole on an upgraded spring guide...the last thing he did for you was anything free.
What if he wired it wrong and cooks the motor...I guess you are suppose to buy another motor aswell....?
Whomever this person is....don't waste your time or money on them anymore and look for a " gun doctor " with some integrity.