I noticed that toothbrushes are often mentioned. Are there any other
kinds suitable for this, like the 2" round parts cleaning brushes, or
is that overkill?


I think it might be overkill... most of the dirt should come off with regular
water and a bit of soap, and any rust should be removed with softer materials,
but taking more time, to be safe. On my S38 (1946 with CW/BFO) I used a SOFT
bristle toothbrush for tougher cleaning, but I took my time. I chose to stay
away from more blunt cleaning methods since I wanted to preserve as much as
possible without adding to scratches and so on.
If anyone's interested, I had to repair some damaged areas of the wrinkle
finish (there were some shiny, smooth areas where the finish had been removed
and the metal underneath was exposed, a couple of inches around on one side and
a half inch on the top)... so I decided to use some black, shiny fabric paint
and stipple it over the affected areas, about three layers of stippled paint,
and when dry, I used a matte finish clearcoat spray to coat the whole thing.
Looks factory!
Stippling involves dabbing some paint on a small sponge or otherwsie rough-ish
applicator (even a crinkled up paper towel will work) and tapping/stippling the
paint onto the damaged area and overlapping a bit into the good surface until
it matches the depth and finish of the original. Only takes a few minutes.
Works beautifully!
BTW, if you need to replace the multi-value filter electrolytic capacitor, you
can use separate electrolytics to do the same thing. Just be sure to note where
the contact points were originally before you remove the old cap. Using four
separate caps is actually cheaper than using a NOS muli-value type.
Good luck-
Linus