a few weeks ago my car didnt start while getting gas but just cranking. I changed the coil and coil to dist wire and we started. last week while cruising the car cut out just stopped running. I fiddled with the replacement wire and it fired up. I got about four blocks from home and it quit again and backfired through the exhaust in the process.
I got it home and let it sit and cool down for a few hours. I changed to another coil wire and it started. I put it away and after having it on my mind I put the second wire back on and it started..... putting it back to the same condition when it stalled twice!

Any suggestions?

It has an MSD 6AL box and I am feeling the problem may be there????

check all the connections, ground, switched and non switched 12v to the ign box. also, you can read about how to test the ign box, either ground the wire and watch for a spark at the coil wire. or short the green and purple wires.
might also try pulling out your rev limiter chip and see if that helps.

mine did that also...ign sw was failing internally.. i verified it by using a jumper wire directly from battery + to + side of ballast resistor when it died the next time,..

car drove fine until i removed wire..replaced sw all ok now.. also check bulkhead connections first.. i had already cleaned all mine

Mine was a loose connection on the blue wire at the ignition switch connector. I got lucky in that my foot brushed the connector and the engine hiccuped.