Yes, I am using the on-line schematic... somewhat hard to read, but the 2 tuner schematics (pages 15 & 16) are pretty clear. I expand the picture as necessary on this iPad. The varicap diodes are fairly easy to locate, just follow the lines from the "tuning" input(s) of each tuner down to the 33k isolation resistors to the VC diodes.
I have no idea how to check them or how to find replacements.
jr