IHC 404 problem

okay guys so my 404 had been running great for weeks . i fixed all the problems it had after i bought it. now suddenly it started to act up. here are the specs of the the tractor new plugs, wire and coil pack , compression is 145-150 on all four cylinders, ran like a champ no oil burning but did have a slight leak from the valve cover gasket as i did not replace it when i put valve guild seals on it, after previous owner rebuilt it and didn't install them. so i was running a box blade and the tractor began to miss though out all throttle ranges. a friend of mine thought it maybe the timing just slightly off he turned it slightly, it smoothed out for about 20 minutes then died. after looking over the tractor we noticed the coil pack was leaking and dripping on the distributor. so we replaced it. the tractor started right up but still misses we adjusted the timing it seems to smooth out until you tighten the bolt to lock it into position then it starts to miss again. if the bolt is snugged up it will run fine for a bit then slowly start to miss again. im thinking that the resistor that goes to the coil may be a problem as it get crazy HOT. any advice would help me i can still start and run it but not for long before it starts to run bad. thanks i cant wait to hear what you guys think it could be. Also this 404 still has points even though it has been converted to a 12v setup :?

A coil that is "for use with an external resistor" is needed. A new ballast resistor from a 1966 chev 6 cylinder biscayne will do well. Your charging system voltage must also be chacked and it should be between 14.2 and 14.8 volta at mid throttle. Jim

Getting hot is how a resistor works. It dissipates the electrical energy as HEAT. That is why it is in a heavy ceramic enclosure.

Does the coil get hot too? If the coil is getting hot that would cause it to break down and cause a miss.