How essential is it to have a perfectly lined up ppf? And also what is the correct method to check the clearance, service manual is ridiculously ambiguous and there doesnt seem be clear consensus on the multitude of threads i read

 

Edit

 

its kind of a weird measurement, but its not too bad to do. there is a flat bit on the little crossmember and then you just measure from that to the bottom of the PPF. they want 75mm, but the range is 70-77mm, so its pretty broad.
it does effect the angles of the driveshaft so its kind of important.

the way i did my miata (similar setup, weirder measurement) was to put a jack under the trans and just raise it up until it was right, then torque it down. use a torque wrench, they want it tight.

 

I've never found a need to align or do anything in particular. Really there doesn't seem to be much if any slop in it, you just bolt it up and it's where it should be.

I typically bolt it up to the diff first then rotate up onto the trans and tighten up the bolts on the trans.

I have seen cases where the PPF was bent, typically from high horsepower cars or cars that did hard launches. When bent the shifter turret in the hole it comes up through in the body is pushed over towards the right side of the car, sometimes bad enough that it's touching the body of the car. With 2 PPF's side by side (good one and bent one) I couldn't see any evidence as to which one was good and where/how it bent. But this can happen. No amount of bolting it up using different methods or trying to align it would fix that.

But, if you have a good PPF, just bolt up and done.

Dale

 

yeah its weird the FD one seems to just go back where it came from.
the miata has like 6" of adjustment range, so the new to you miata is way off