Also, looking a bit more closely at your schematic, it seems that most of the component IDs are written in ink, not printed. You may have a prototype. The 272 is probably a sequential number for all the amps Ampeg did that year.
Yes, you're correct.
Based on what I've learned about 'em, this is a very early Reverberocket. Another clue is on on the tube chart (the handwritten "R" after the model), because they did make R-12 Rockets before they made Reverberockets. They used a Rocket label in this one and wrote an R there. This info I got from Ken Fischer (RIP), who worked at Ampeg when these were being built.
Being that the Reverberocket was the first amplifier built with onboard reverb, it makes this particular amp pretty kewl.
I'll take a peek under her skirts tomorrow when I get some time, and record some voltages.
Here are pics of the PT and OT. It does have a PT-106 installed.
'926' on the PT is the EIA code for the manufacturer--Todd Electric Company of Yonkers, NY. '129' is the production date: 1961, week 29.
'682' on the OT is the EIA code for Electrical Windings Incorporated of Chicago, IL. '112' means the 12th week of 1961.
More info as I get time... Cheers!