Here's the v2 schematic, with some comments by me on the changes:
As you will hear in the samples, the amp ended up sounding dark and a little bassy. I partially attribute that to Peavey's design--their speaker rolled off bass frequencies quite a lot, and maybe they designed the amp around that.
I've tried to combat that: C6 dropping to .01uF, and I'd still like to go smaller. I increased input impedance at R2 as well.
The stock opamp stage can clip the power amp stage fairly easy at a setting or 7 or 8, and it really sounds like ass. I changed R9, decreasing clean channel gain, so that doesn't happen as easily. More of a cosmetic issue, but I like knobs that are useful at 1-10.
The first tube stage is largely unchanged, just a tweak to R50 and R57 to get the input signal right. The second stage changed a lot. I went using a fairly small resistor off the plate, followed by a bank of LEDs that limit the signal to 2V and thus cause clipping, then followed by the post level pot, VR3, which I increased to 50K. The cool feature is that VR3 not only trims the level off the tube stage, it also changes the amount of tube gain. So at a low setting, say 2, there is lots of second stage level, which causes the LEDs to clip, but then the signal will be strongly attenuated at VR3, so the overall volume is low.
The net effect is I can dial in any tube tone from clean to dirty, and also select LED clipping for distortion, all with two knobs
That is the cool feature I'm going to incorporate in my tube pedal designs.
You will hear in the samples that the clean tube tone is really dark. That is partially my guitar, but still it's much darker than the clean opamp tone. I initially thought it was just the tube I picked, but now I suspect C39 (a stock Peavey cap) is way too big after I changed the value of VR3, so I'll probably change that to something much smaller, or even remove it since I can't figure out what it is for. Perhaps Peavey needed it for their lead channel, which was opamp and diode driven
The reverb section
That was the bane of my existence. Yesterday I redesigned and rebuilt that thing twice, in an attempt to get a reasonable sound. Those things are a pain in the ass--you hit them with 8V and they give you 5mV in return
And they are noisy as all get-out to boot
I'm still trying to figure out grounding and isolation for that thing, because it imparts a nasty high frequency buzz if the knob is set north of 3. I'm looking to increase C15 as well, to drastically dump highs from the reverb signal so I can preserve them in the main signal.
The other reverb changes were the addition of two more transistor, solely to complete isolate the reverb from the rest of the circuit. In Peavey's empty holes on the PCB, they only left space for one more opamp, but I don't see how that can be done while driving the reverb hard enough and isolating the return circuit
Transistors are my new best friends.
Overall, I am pleased, but there are still a few bugs that wouldn't be acceptable for a commercial product, the reverb being the biggest one. Also, there is crosstalk between the tube and clean channel when the tube pre knob is set above 7. This is understandable, as the level going into the second stage grid can be 20V or so
It's kind of a cool "feature", you get a clean attack with a soft heavily distorted sustain
Also the increase in the VR3 value which did all those groovy things to the tube channel causes VR3 to be active as a post control on the clean channel, but not in a good way--for some reason not understood by me (my best guess it that annoying reverb input stage impedance), it causes clipping when set low
So you get a quiet clipped clean channel that doesn't sound good. I solve the problem by leaving the post gain on 10 when I use the clean channel
This is a practice amp with no footswitch, so no harm done.
Please note in reading the schemo that towards the end I got a little crazywith trying to keep up with changes I was making, so I didn't bother straightening out the numbering system. Thus the C15 I was referred to is the lower one
That is all, on to the audio!
It's my fault for trying to use the same rail for the bias and the heaters
I have to give a lot of credit to Peavey, I called them twice, first time to get the schematic which they emailed to me right away. The second time I called ordering parts, I needed another pot for th e reverb (recall the PCB was designed for a reverb option, so there was already holes for it, I just needed the part). They didn't use the old style knobs anymore, that's why the reverb knob is black. Anyway, they only wanted $3.02 for the pot and knob, I got it a few days later, and then they didn't bother to charge me 
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