So i hate these threads but im completely stumped....

Car: 1991 Honda Civic Si
Brief overview of my engine:
D15z1 block
ZC pistons
D16y7 head
D16a6 intake manifold/fuel injectors
d16y8 DC Headers
OBD0 D16a6 Distributor
wires for a D16y7
plugs for a d16y7

(pieced together from **** in the garage, ran perfectly for a year, literally no problems)

My car has been running really rough, like it is misfiring on one cylinder. My distributor o ring had failed and my dizzy had quite a bit of oil in it, and the cap gasket had a 1" gap in it and i drove it spiritedly in the rain (obviously not knowing about the gap). So that would explain why it misfired at first but I've since dried out the distributor and cleaned the cap and rotor off, they're now sending spark to the plugs. I replaced my plug wires since their resistance was half of what it should be, and i replace the plugs since the car runs a little rich rich (about 15.5:1 fuel air) and they were pretty soot covered and i wanted to replace them just to make sure they we're not the problem. My spark is a little yellow but mostly white/blue, i checked spark at the plug boot, and at the dizzy cap (cap spark was much more yellow).

I did all of that and the car was still running rough but it feels like they're all firing but one of them isn't running correctly, like theyre almost running on 3. The gas smells more rich than usual too but better than before i cleaned the dizzy and got new wires/plugs. I even tried Seafoaming the fuel system as an act of desperation, didn't do much. So i got my compression tester.

I did a compression test and these are the results:
cylinder (from the front of the engine to the trans side)
1: 135 slight oil deposit on the new plug
2: 135
3: 135
4: 118 no deposits of fluids

I'm gonna get a feeler gauge and check valve clearances tomorrow. Could it be a head gasket? If a head gasket goes out wouldn't there be fluids burning? Could the spark be not strong enough?