1995 Mustang V6 - Cyl #3 Misfire - Help!

Hello Everyone-
I have searched around and have been unable to find possible solutions to my problem.
To start off, I acquired the car about a year ago, with about 60k miles. It sat for an extended length of time before I acquired it. When I first got it, I was told it had an oil leak. After inspection, it did have a bad oil leak, as the oil sending unit was broken and oil pouring out. I repaired this, and drove the car roughly 1k miles with absolutely no issues at all.
Then, on my way back from a trip, the car overheated. The needle never got to the red, but it did get close, and as I was in a very bad location, I had to continue driving a short distance, after turning the heater on (which I believe kept it from getting into the red), before I could pull over.
As I was slowing down to pull over, the car died. At this point, I knew I was screwed.
Skipping ahead, I took both heads to the machine shop, and they did shave a small amount off of them (I can't remember exactly how much they said). There was no coolant in the oil, and there was no oil in the coolant, but I had very low compression on multiple cylinders. Also, I had to replace the cooling fan, as low speed was gone.
I cleaned up the rest of the parts, and not familiar at the time with the head gasket issues plaguing these engines at the time, I replaced the gaskets, and put it all back together. Filled back up with antifreeze/water, got all the air out, car would run. But initially, it ran really good. Soon, it developed a small skip/misfire, which over the period of a couple weeks, progressively got worse. Temperature stayed normal during all this time.
I ordered better head gaskets, the 3 layer gaskets for the 99 V6, and tore it all back down and installed new gaskets again, from the heads up.
The skip/misfire is still here, and the DTC is still saying Cyl #3.
I put a small amount of oil in Cyl #3, tested compression, and the compression was a small amount higher, but not by much. So at this point, I'm not certain, but I am thinking my rings are alright.
Also, while cleaning and putting it all back together, I did lap all valves, and they all appeared to be in great condition (visually).
I have ruled out fuel injectors (swapping #3 and #4 injectors), checked 3+ times visually and with starting fluid for vacuum leaks, finding none. Ruled out spark plug wire by replacing with new ones. Ruled out spark plug on Cyl #3 (even though I did put new ones in), I swapped #3 with #4 anyway just to make sure.
What are my chances of a cracked/warped lower intake?
Any other ideas or suggestions?

Thanks in advance!
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It's very low I am sure, based on my compression tests after the first head gasket change.
But, I am currently at work, and when I get off, I will test all cylinders again and post the results.
Should be in about 2 hours, considering the rain holds off long enough.
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Alright, compression test results as follows, and they aren't so great:
Cyl 1 - 185
Cyl 2 - 155
Cyl 3 - 90
Cyl 4 - 95
Cyl 5 - 140
Cyl 6 - 190

I did fail to mention that I do refer to the FSM for torque specs and I do properly torque each and every bolt per spec.
Leak down results are as follows:
Cyl 1 - 20%
Cyl 2 - 76%
Cyl 3 - 92%
Cyl 4 - 92%
Cyl 5 - 70%
Cyl 6 - 28%

It was difficult to hear where all the air was going, but in all cylinders except #3, the air was escaping through the valve cover, where I took of the oil filter cap. I could clearly feel the air blowing out here.
Cylinder 3, most of the air is escaping through the intake manifold out the air intake, in which I could clearly feel it escaping here.
I'm not an experienced mechanic, I am learning a lot as I go through all this. But how is this car running so well? It has a bad skip especially at lower rpms, and backfires through the intake some. At higher rpms (2500-400) it's fairly smooth and has a good bit of power.
Possibly cam lobe is bad?
Never heard of this happening on a car with roller lifters but not much left to check.

Did you replace the O-rings on the fuel injectors?
You may also want to try replacing the connector on the #3 fuel injector.

You may have a vacuum leak off the engine which leans it out causing a misfire which only shows up on #3. Check hoses going to the fuel tank vent and canister. Check to see if purge valve is stuck open.


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