1993 f150 power issues

First change the fuel filter and see what it does. Otherwise the fuel pump may not be putting out enough pressure. Fuel pressure would need to be checked.

I already changed fuel filter and pump, I don't have a fuel pressure gauge( lost) and won't be able to get one til next week. I do have a timing gun and will be checking the time today

Ahh then I don't think you have a fuel pressure issue. Check the catalytic converter. Drive the vehicle so it get warmed up, park in a dark area and look at the cat. It would have a orange glow to it if it is plugged up.

The catalytic converter exhaust manifold air pipes are all new, changed distributor cap and rotor and it fixed 70% of the problem just can't figure the rest out

Well the next thing to do is look at the EGR Valve system. Make sure the EGR Valve is working, take it off and clean the center pentle so it can close, make sure the diaphragm is good, and clean out the port for the EGR Valve.

I have already done the egr valve and solinoid, at certain constant speed on level surfaces it starts to shutter, also the muffler vibrates at idle

I forgot to tell you to check the timing.

Timing is good

Well then I would check the compression of the engine. May just be getting tired.