My 305 SBC stumbles when hot

I have a 1979 Chevy El Camino I replaced the intake to a edlebrock 2101 intake and freed up the exhaust. Today as I was coming back from a road trip the car started stumbling to almost a dead state when I would get on it. What could be the problem? I am at a loss and this is the only mode of transportation I have.

The first thing I’m going to ask is, does the gas you’re using contain ethanol?

Tester

It’s standard pump gas. 87 octane.

But does it contain ethanol?

Tester

Check fuel pump pressure and inspect the rotor and cap.

I had replaced the rotor and cap when I did the intake swap about two weeks ago. Could the coil being going as well? it’s only a 20 dollar part that I could throw at it, I don’t have a way to test the fuel pump.