97 Ford 460 issues

I have a 97 Fleetwood pace arrow vision on the Ford F53 chassis with the 460 v8 gas engine.

33k miles on rig. New aluminum 80 gallon fuel tank and FoMoCo sourced fuel pump. After driving for roughly 2 hours I lose power and can't get over 2k rpms without the engine bucking and shaking, if I continue the check engine light will come on.

If I shut off the engine for a minute or more all is normal again after restart though for how long varies.

I did have a problem with the distributer bolt being loose and the timing getting messed up which I set as well as I could as due to the design of the dog house I can't get anywhere near seeing the timing marks without putting my face into a spinning fan blade. If anyone has a suggestion on how to fix that issue also I'd appreciate it.

Oh before anyone asks the rig is OBD1 even though it's a 97 so pulling a code without the check engine light on doesn't work