Vintage Synth Repair

So it turns out, looking around for info on those ICs, the 7805 and
7806 parts have the the metal tab connected to ground, the 7906 has it
connected to -6v... Its strange because I don't remember removing any
insulators from it when I disassembled it.  I remember the parts being
stuck to the heatsink with some sort of glue, but that was a long time
ago so I might be mistaken.

Jammie, specifically I'm measuring the wire on the ribbon cable that
goes to the rest of the synth that I've traced back to the output leg
of the 7806.  If should be +6v but its more like 16v.  Unfortunately I
am unable to find a service manual or schematics for this box.

So the next thing I'm thinking is the caps.  There are a total of 6
caps in the PS,  three 2200 uF 16v electrolytics... these were
obviously blown out when I opened it up and I replaced them.  They
connect the input legs of the ICs to ground.  There are also 3 dipped
tantalum caps connecting the output legs to ground, the value is hard
to read because they're pretty close in there with the other parts..
I'll bend some things around and look closer tonight.

I'm not sure quite how to test the caps.  Looking for shorts with my
DMM and testing them in circuit with the power off, the large
electrolytics give me a steadily rising resistance in one direction
only.  The tantalums seem to have resistances of 5k, 7k, and 10k.

Hugh, I really appreciate the invite.  I'm in Saint Louis, MO.  I'll
try to take some pics but I'm not sure how good my cellphone is at
taking macro shots.

Thank you all.
Christian