It was running ok, now it’s terrible, I need help!!!

Have you checked the condition of the fuel in the fuel filter? Might have trash and rust in it.
Hi
Thanks for the reply
I have a glass fuel filter and the fuel and filter element look clean, I’m going to pick up a valve cover gasket tomorrow. I’ve adjusted the valves on a couple of hot, running 218 flat head engines, you have to crawl into the wheel well and work under the exhaust manifold… the slant 6 should a bit easier (I hope).
Thanks
Bill