Restoring Heathkit AA-32 Vacuum Tube Amplifier

I was only solid state guy until I stumble into this little guy with 8w/ch. It was completely beat up when I got this unit. Volume was scratch and there were low hum on both channel. And sound was distorting in mild volume ( half of 8W??). I found Heathkit AA-32 has bad multisection power capacitors.

 I redesigned power supply unit and ditched multi section capacitor. Because currently available multisections are way behind technology in terms of quality and temp ratings. Multi sections are only good for keeping vintage look.  I used Nichicon Caps for voltage doubler and  Resistor Capacitor filtering circuit. .  I replaced drippy carbon resistor to Ohmites with same value but higher wattage rating. I designed PCB and etched it in HCL( muriatic acid from Home Depot)   and drill it with Dremel with 05mm bit. Mean time I painted transformer covers and clips with Restolium spray paints after wash with rust remover from car body work supply. All of Lytic caps under the chassis has been replaced with same value high temp caps from Nichicons. I hooked up new power supply and power up the amp. Amp run really good for few hours then developed loud scratch sound and thumps which was independent of volume level. I was not sure of problem source. I put away amp for some time.
Last night 1/23/11, I reexamined all solder joints that I made when I replace power supply. I found one cold joints. Repaired cold joint and fired up AA-32. It is singing like a canary.  I just need to mount power supply board  securely on the chassis to finish up this project. Coupling caps AA-32 uses are 9 of 0.1uf 400v caps. I am thinking about replacing all of these with Orange drops. That will be complete end of this project.
1/24/11
I grew to love this little amp as I listened more. But I am worry about replacement valve for 6GW8. This is pre and power tube combined which is not sexy these days. There are plenty of 14GW8s available for old TV circuits. 14GW8s are 13.5v heater with same core as 6GW8 (6.3v heater). I need to install 13.5v heater transformer  to use 14GW8s in Heathkit AA-32. This will be new project when I need new tubes.