Here's my first amp build - a JTM45 to 1965 specs (well, as close as I could, anyway).
After getting a feel for the time and effort that was going to be involved, I decided to give it the NOS treatment as best I could. That approach has it's pros and cons as I found out. It's extremely satisfying once it all comes together, but having to scour the Earth for unobtanium is a looooong and frustrating exercise. Another unforeseen consequence of the a la carte approach is that you can't just follow George's excellent instruction manual "paint-by-numbers" style (that's something that other noobs who might be considering the same approach might want to keep in mind).
I actually had to understand what the wires in the original-spec transformers did which required a lot of extra research (but at the end of the day that's a good thing). Original spec trannies and NOS power tubes also mean the test voltages are going to be different from those in George's instructions (it seems George spec'd slightly lower rated trannies in his kits to cater for modern-day power tubes which don't have the power handling of old glass). No biggie though if you can get access to the test voltages from the original Marshall schematics which can be found in the back of Michael Doyle's "History of Marshall" book.I eventually managed to cobble together a full compliment of Piher and Allen Bradley resistors, Mustard tone caps, and Radiospares silver micas, which found a home on a brown paxolin board that I drilled and turreted. The silver mica on the high treble pot is a temporary measure - it will be removed and used on my next build (a JMP50).
The glassware is all NOS GEC KT66s and Mullard ecc83s and gz34.
I used M e r r e n Drake replica OT and PT, and a ClassicTone 3H choke that was as close to the originals as I could get.
The faceplate is supposedly an old replica of a 1965 JTM45. Naturally, the holes didn't quite line up with the holes on the Valvestorm chassis so I cut the front of the chassis off and had a new front fabricated and welded on. Soon after that, the Sparky faceplates became readily available on Valvestorm - DOH!!!!
The head and speaker cabinets were made by Jeff Swanson and in a word they are simply stunning! I went with the Series II 2 x 12 extension cabinet just for something different as it has a really cool vintage vibe. The speaker cab is Jeff's open/closed back convertible design for maximum versatility.
I asked Jeff to use EC Collins grill cloth on the speaker cab. That stuff really is a dead-ringer for the original Marshall pinstripe cloth (and nothing like the repro stuff that Marshall uses on their re-issues these days).
Hiding inside are a pair of Scumback M75 paper voice coil speakers to approximate as closely as possible the Celestions that Marshall would have used in back in 1965.
I know my lead-dress is not quite up to par with some of the amazing examples I've seen on this forum, but all in all, I'm pretty happy with how the amp turned out given that I had never even picked up a soldering iron prior to this. And aside from a couple of minor issues, it pretty much worked first go.
So on that note, I have to say a big thank you to everyone on this forum for providing such and incredibly valuable source of information without which this amp never would have been possible.
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