[mr48chev]

And any or all of the above mentioned things will cause the miss or rough running you are experiencing.

The heavy (10 gage) wire to the distributor from the ign on pole on the fuse block is a must. Also make sure that it is firmly connected to the "batt" pin on th cap. I am having issues with mine right now as I have an old Hei primary wire off of a doner rig that has the clip to hold it on the cab broken. Every once in a while it gets just loose enough to cause the engine to die or miss. I've gotten pretty good at pulling to the side of the road and reaching in and giving the wire a push back in place and going again.

The wires on the pickup coil that Neba mentioned bear checking if the thing has some miles on it. That exact thing was a nemesis for me on one engine running problem for a customer and it took another mechanic in the shop to bring it to my attention.

I'd change the fuel filters just as a matter of course and I put one between the tank and fuel pump on everything I have that didn't come with one there originally. On a rig that has been sitting for a number of years you can expect crud in the tank.

That carb has been sitting around for the past eight years either in the box on your shelf or sitting on the engine. That makes it eight years old which isn't exactly new. You may have low or few miles on it but it may need to be freshened up with a new kit.

Also the plugs are six years old and if you only made short runs with them or fire up and run they may need to be changed.