Changed intake gasket, now it won't start

First of all this can't be from changing the intake gasket. Unless you did something like left a rag or something stuffed in side the intake when you are cleaning it? Without being there I'm just at a loss for ideas on how your motor could be running ok before the intake gasket and then running worse after fixing the intake leaks. Unless the car was Tune with intake leaks? IF it was me I'd be taking the motor out but I'm not suggesting you do that but just saying if it was me....
It is running worse, but still runs. Some people might think it is running fine but I can tell something is up. Pulling the motor might be a winter thing, last resort kind of option. I have never rebuilt a motor but my father in law has many times. Only issue is I have no equipment to pull the motor with.

Im going to try everything I can first. Thus the carb stuff and the plug wires. Plug wires are rather new anyway but it only sets me back the cost of the wires to try. They are way too long as it is now.