According to my '69 parts manual the original # is/was 3431-020, same part for A,B, and most C bodies. I am sure this has been superceded several times.

So, it very well could show up as for a later C using that 3501 number.

They seem to be a pretty generic part, looks much the same as the one for my '85 D100, and same as the one in the 92-93 D150 spare control I have laying around.

I am sure you have noticed it, but it looks like the clip that holds the vacuum lines in place is askew, possibly shorting across some of those bare terminal ends?