Silvertone 1474 - First restoration

Several years back I bought a Silvertone 1474 that works great. With it came this extra chassis. I pulled it out of the basement in hopes to start my first amp restoration project. After taking a look a little closer, two things are apparent to me. This circuit is different than the working amp in some minor ways, and it appears someone has not only been in this chassis before to add three pronged cord and replace caps, but also modded some things. Unless the I'm completely missing the caps in the schematic that run from input jacks to V1?
Well, I'm missing at less one OT. Not sure if the other is any good or what the specs are on these. I suppose I should test the PT too...
Do I replace all the iron? Can I test the PT without power?
Also best method for cleaning knobs and chassis?
Any pointers from the pros would be more than welcome. What order of business do you usually approach something like this?

 

more pics and schematic
http://www.prowessamplifiers.com/schematics/silvertone/Silvertone_1474.html

 

Well, didn't get a ton done today. But had time to connect the mains, fuse, and switch properly to verify that the power transformer worked and find the voltages of the secondary windings.
375vac on each red lead. There is a center tap.
7vac between the green leads
5.6vac between the yellow leads

I checked the dc resistance of the choke. It reads about 45ohms. Not sure I have any other equipment to test it's inductance etc.
I'll probably work from this point through the power tubes and stages trying to clean things up and make sure my lead dress is neat.
not really sure what a 5u4gb will rectify at. Anyway this project of fun already