Slant 6 power issues

this happen over time or suddenly? Something changed out?

I'm assuming this is in an old car with no cat converters etc?
You could take of the fuel line inlet to the fuel pump, run a line into a gas can of clean gas and that will answer the gas question for you.

You might have a vacuum leak. you have brake booster?
No I don’t have power brakes. I probably have plenty of vacuum ports to plug on the carb tho. It’s a 74 but I’ve disconnected all the EGR stuff. It happened after I replaced the oil pump gasket. Had to pull the distributor to get to it without pulling the motor out. I’ve got it back in time though. If I adjust timing either direction it runs worse