Stumbling 3.4

Hey guys I have exhausted everything I know on getting this truck to run right and need some help.

This is actually a 3.4 swap into a 91 pickup. Motor is from a 98 4runner. It fires up great just like it should than a second later after initial fire it starts stumbling and running really rough and very rich. Unfortunately I never heard this motor run prior. I am helping a buddy out and did the swap for his daughter. Last night with obd2 scanner plugged in it didn’t set off the cel but I did get a p0305, cylinder 5 misfire.

Here is what’s new: plugs (denso), wires, swapped a new coil pack around, double checked grounds, swapped maf with another one, fuel filter, new fuel, fuel pump, no vac leaks, cleaned throttle body and iac valve, tested cylinder #5 injector it’s at 15.9 ohms. Timing bet is new but I am confident in alignment and spun the motor over by hand when it was out.

It’s like it fires on all cylinders initially than runs on only 5. Revs ok still has the miss and is not throwing any other cel. I guess a compression test would be in order at this point?

Thanks in advance!