After much measuring, checking, test fitting and re-clocking the starter so that it clears everything properly, I installed it and tested it and all it did is go click click. However after measuring the depth one more time, I decided to install the .065" spacer ring that comes with the pm starter, believing that the clicking was caused by the pinion not having enough free travel room to develop velocity before touching the flexplate teeth. It turns out yes that's exactly what it was. The cranking sound is so nice oh my god, I'd forgotten what my car is supposed to sound like when I hit the key. Lol
The powermaster mastertorque starter comes with a 10 tooth pinion that is 1.155" diameter, while the 9 tooth pinion that comes on the other aftermarket starter I had and all three of the OEM style 1990s 302 starters I tried, are only 1.05" diameter. .105" is a huge difference, considering that you're only supposed to have a max of .035" clearance in the mesh between the gear teeth! That was the whole problem all this time. I don't understand why the pinions are different diameters because I ordered the powermaster for the 157 tooth automatic. The same thing I ordered the other starters to fit, so whats up with that?? After testing the starter many times and it got warmer it did the click click thing a couple of times so I believe it may need an increase in shim thickness perhaps to .075" Or maybe it just won't get that warm again I don't know. The engine never started during testing because it had no fuel connected. On a related note, I learned that this style of starter does not retract by itself from the flexplate once it's meshed it needs to be kicked out by the engine running so if the engine does not start sometimes the pinion will just stay engaged with the flexplate. I read about that the other day. Anyway, to summarize the pioneer plate seems to be decent, but be careful of the welding beadys! If you put a new plate on there check it very carefully along its teeth and remove any of those little beads of steel that might be stuck to it because you will not like it if the starter pinion engages on those. It could destroy things. I have a feeling this is why a lot of people have problems. Both of the last two flex plates I got had those stupid welding beads stuck to the gears. The powermaster starter I used is number 9603. I no longer hate starters quite as much. Oh I almost forgot, It's very important not to make a simple jumper wire on the starter solenoid, if you're going to use the original Ford starter relay as I do. I do not like the idea of having an unfused heavy hot wire going down to the starter it seems a little scary. So the wire that comes from the ignition splits one part goes down to the starter solenoid and the other one goes to the factory Ford solenoid so they both get hit at the same time, and both release at the same time. If you use that little jumper wire on the starter what happens sometimes is right after the engine starts there is a moment when the engine is actually turning the starter over and being a starter motor it will act as a generator in that moment and guess where that 12 volts of power is going to go? Yes straight into the jumped solenoid. Which means the starter won't disengage and will keep running as a generator until you shut the engine off. Not fun.