I don't think it is water in the gas.

Check to make sure the wires are good and tight at their

connections, especially the coil wire.

Did you adjust points or timing? Could there be moisture

in the distributor cap? is it on tight?

Plug gaps very wide could do something like this also.

Fuse boxes on 122s are notorious for being a beehive of

bad connections. Some guys drill out the rivets, and

screw and solder them together. I believe that one of

our folks even sells soldered 122 fuseboxes but since I

soldered my own before I found out about him.....

This is probably the cause of your amp light being

dimly lit. BTW most 65 122s have generators, not alternators.

Yours may have been changed.