Need pointers on an Amp Mod

[MakoML]

Would really appreciate any input you guys are willing to offer to make much needed EVHish "improvements" to my little Marshall Class 5 combo. I can send a stock Schematic via PM or if its ok with the mods, post it here if you are willing to take a quick look at it and suggest some simple changes to make it feel and sound more like a 12000 series amp than it currently does. ( I know this is not entirely possible, but want to get it as close as I can)

There is already a guy named Lyle Caldwell that has some simple "plexi" styled changes but they are not really EVHish in nature.

I use this amp for practice with both with the little 10" combo speaker and my DG style strat with pedals, and with a Hard Ash Franky clone Floyd equipped guitar with the EVH Franky HB thru an old Carvin 4x12 with Celestion G12M-70 speakers (blah). What I love is the headphone out is actually a 0.2 watt low power out and I can crank the amp into the 4x12 where it shows EVH type promises for sure.

The issues I have are these: The bass is flabby and horrid, usable range is from 1 to 2 on the knob, past that and it becomes awful. It doesn't matter if its the combo speaker or the 4x12. On the Volume/Gain, at 7 its at full volume, and anything beyond just adds a fizzy type distortion. I would like to get that smoothed out into something that is EVHish at the least. I'd like to get it to sound its very best dimed like a real 12000 series plexi sounds.

Anyway its a pretty simple little circuit board and I can solder pcb's without trouble. I just don't know enough about tube amps to know where to begin. I plan to do a tube change soon with Mullard Reissues for both 12ax7's and the EL84, and change the speaker to a 10" Greenback so I will make any promising sounding suggested changes while I have it torn down.

Thanks to anyone willing to give some input.

http://www.marcuslocke.com/Guitars/C5_C ... iagram.jpg