[Radioroslyn]

For this set you don't really need an isolation transformer as the power transformer isolates the ac line from the chassis. Typically, you'd use one when working on sets that don't have a power transformer or have series wired heaters. These sets will have one side of the ac line connected to the chassis (early design) or a floating B-. This means that one side of the line is connected to the - side of the power supply and most of the - returns. Sometimes the chassis ground is used for a rf ground. You might find a small amount of ac volt between the chassis and ground. This is from #69 passing a few micro amps of the 120vac. It poses no shock hazard if the therein are not leaky or shorted. When leaky they act as a resistor and couple the ac volt to the chassis...

As for the blocks : Bakelite Capacitor Rebuild Without Desoldering – Philco Library (philcoradio.com)
Antique Radio Film Capacitors for Sale (tuberadios.com)

Use the parts list as your guide for buying. The micas in the front end should fine. There are 2- 110mmf #39 & 40 I think they are foil/paper caps in disguise. 67A is a 1000v job. I don't really know it's there for but I'm not a designer. If you wanted to replace it w/something tubular, you could restuff w/two .002mfd 630v in series. This would give you .001 mfd @ 1260v. Gut the Philco cap and reseal the ends w/ brown hot glue. It's used to glue on women's hair extensions. #69 use safety caps (XY rated) when they fail, they fail open not short and explode. The filter caps I'd go w/ 2x 10mf @ 450v and a 22mf @ 450v.

The resistors are spected @ +/- 20%

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