My '92 sometimes runs rougher when it's hot..or seems to have less power but I imagine it's for much different reasons, so let's worry about #2 at the moment, it could be serious (or not)
You didn't mention how you tracked it down to #2? If you can run through exactly everything you've done, there may be an omission there someone here will pick up on...
If you're sure it's the no.2 plug you checked which was clean and dry, that might perhaps suggest that there's no fuel getting to that cylinder, OR that it's not that cylinder that's missing (sorry, humour me here)
Have you had any check engine lights coming on? Do you have a Ford engine code reader, or is there somewhere you can get them read? As a '92 even if your engine is bigger/different from mine (302) you should have an EEC-IV computer which means with time, patience and a voltmeter (or you can watch the CEL) you can translate the codes without much gear at all,(if you search the forum there's instructions there) but it's important that you check it NOW if you haven't - it'll tell us what else might be going on....
The other question is, is there definitely spark to that plug? You haven't changed the distributor cap or rotor so both must be checked. You also need to ascertain whether fuel is getting to, and through the injector. I'm not up with the best ways of checking this without replacing them or having the injectors all cleaned (which wouldn't hurt) so hopefully others will make suggestions for that.
Meanwhile, you're not giving us a lot to go on, can you tell us more?