1952 Midwest CV-20/NV-20

[wdln]

I am looking for a schematic or service manual for a 1952 Midwest CV-20/NV-20. These were sold direct from the factory via catalogs and are therefore somewhat rare. My understanding is that Midwest was pretty successful on the radio side but by the late 50's they were out of business, after trying their hand at TV. The 1952 catalog page I found offers two models for sale... the NV-20, which was a fully-assembled floor-standing TV, and the CV-20, which was just the fully-assembled electronic chassis for DIYers who wanted to make their own cabinet. The only information I have is a tube diagram, which indicates the CV-20 nomenclature.

The unit powers up and the picture tube (20CP4) has good contrast, but there is some audible arcing in the high voltage section and the picture is not stable vertically or horizontally. I have replaced most of the paper caps underneath the chassis but I'm down to the electrolytics, and here's why I need a schematic.

There are four can-type caps on the chassis, with one additional electrolytic mounted normally under the chassis. Two of the cans are stamped with values and terminal legends so they'll be easy to replace; I haven't decided whether to re-stuff the cans or just do it all underneath. The other two are unmarked, and I can see where there used to be a paper label of some kind on the outside. One of these has 4 terminals and the other has 2. Without a schematic, I'm not sure how I can divine the values from these. I do have a meter but I doubt they will measure properly, being that old.

This set was stored in a hot/cold garage with a bad roof for many years. I'm lucky it powers on at all, but that's probably why the labels are gone.

So I'm either looking for a schematic or some helpful suggestions/tricks to figuring out what these are. I've attached a photo of the TV as well as the tube map. The caps in question are CE-20 and CE-10 on the diagram.