[Davidra]

Well....it might be agood cap (shown with an error of not in fact connectingto the B+, no tiedot) but it is immaterial - it is missing in the chassis.

I suppose I should clarify. There was no cap where it seems like it should be but there was extensive prior work with multiple non stock caps so it is a little hard to tell.  I restuffed the metal cap blocks and scavenged bakelite blocks from a parts set and reatuffed them too to try to get back to factory appearance. 

Sounds like it will not burn down the house to power up the set without the mystery cap. Thanks again to everyone for their help. I will post a pic of the chassis when I get a minute.