I know alot of good places to get amplifers part -{trannies caps and chassis etc} Stephen at Trinity is a great guy to deal with and has a variety of Matchless inspried stuff clones and trannies and boards etc for builds.
I am sort of simultaneously studying ampbuilding and repair right now as well as luthiery -
{I wanna corner the building and repair market - no just kidding it just interests me}
I have tons of information on electronics {books whose copyrights have expired, but are still very relevant and other things that could be helpful to you}
So just PM me and I would be glad to lay some info and resource tips on you. I never thought i would see a gear head here!
Cheers
Charliewood aka charliewired in amp circles