Opportunity to buy an old valve guitar amp

[pwdrive]

Just to double check, I am proposing to revert this amp to the black faced (bf) spec which is to drop the 40uf cap to the rectifier valve to 22uf (nearest to 20uf). The bf version operated at 50v lower at the rectifier which means the amp has slight less output, distorts earlier and sounds a little sweeter.
Any thoughts
Rob

Rob, are the differences you quote above the only differences?
If dropping the reservior capacitor from 40uf to 20uf then bear in mind the wide tolerance swing of electrolytic values in general, you might have to select the capacitor using a capacitance bridge

Lawrence.