Triplett 310 VOM repair

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I'm working on a pair of beat-up Triplett 310 VOMs that don't respond to voltage. 

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I've popped the front cover off, but I can't figure out how Triplett intended us to work on the darn thing.

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There isn't enough slack in the wires to fully separate the front from the back.

I'm thinking I'm going to have to unsolder some of the connections to the ohms adjust pot and add extension wires in order to troubleshoot the thing. Am I missing some trick of the trade for working on these?

Oct 12, 2013 update

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No tips were forthcoming, so I started unsoldering wires and removing the mini banana jacks from the bezel.

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I got the boards separated from the rest of the meter. The movements check out OK.

I started measuring the resistors on the board, but the earliest manual I could find online was for a type 3. It was hosted on a pretty sketchy site, too, and was a set of JPEG scans. 

The type 3 manual doesn't match the layout of these PC boards, nor are all the component values the same. (The input divider does seem to match, except that these have a 1200 volt scale versus the 600 volt scale on the type 3 and later.)

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I think this board is from a "type 1" (technically, just a plain "310").

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I think this one may be from a type 2. At least, the layout is different from the first board.

Does anyone know of an online source for 310 type 1 and type 2 manuals?

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