It's been a bit so updating this thread. Got all 4 carbs completely disassembled, soaked and rebuilt. Definitely had more crud blocking key passages.
Discovered that fuel pump was not delivering gas, so need to get a new one.
Gravity fed the carbs and at first she didn't want to start. Checked all four bowl drains and they're full of gas, good there.
Checked spark plugs and was only getting spark thru cyls 1 & 3, nothing from 2 & 4. Grabbed probe to verify spark was getting to the plugs and then found that no spark at all from any of the wires, even cyls 1 & 3 that minutes ago were firing.
A few minutes later was preparing to check the coils and when I cranked the engine she wanted to start. So I let her start and she ran ok on all 4 cylinders. Lots of backfires/pops so just held throttle around 1500 rpm. I'm gonna add Techron to my gravity fed gas supply to help clean her out.
Anyway, I gotta figure out why it's intermittently not giving spark. Thanks again for all the help!
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