I actually left those caps in place on my pair of QuadII's ,
they must be 60+ years old by now , still going strong ,
There a Drilytic with etched foil .
You might well replace them with something of larger value , but remember theres a maximum capacitance that a GZ32 will stand at the output , moving over to a GZ34 might be a plan , it has a larger maximum value of capacitance , and higher current capabillity ,so you might end up with slightly higher HT voltage , and slightly reduced noise ,compared to the original parts .
none of that is a problem .
There are a few companies that do multicaps still , it might be worth checking the available options if you want to keep historically correct ,
Sorry just saw your later posts ,
Halt a minute , have you checked the max allowable capacitance of a GZ34 ?
its 47uF ,
Also those brown foil bypass caps , they look like 250v parts , if the are its a little low as the HT rail sits around 330v on the Quads.
Your workmanship is first class , but dont you think 70uF after the rectifier is a bit much ?
While the extra few uF will help smoothing noise it might also shorten the life of the rectifier tube , because the current on the peaks exceeds the max allowable .
Typically this ends with a spectacular lightening storm inside the rectifier . so be very carefull .
We didnt see the voltage ratings of the caps you used , Id choose at least 400v in this case .
The other thing is a modern high voltage electrolytic is designed for SMPS , modern construction means lower ESR than typical vintage parts , that only serves to exacerbate the overload on the peaks in the rectifier , and bring your beautifull amps to smokestack/lightening ,which you dont want .
let us know how it went on after that !
