Coil, module, bad distributor, and the TFI (I think that's what it's called) are the most common. I know the module can be checked at the parts store, not sure on the others.
Car does look bad ass! Get the hood on there and take some more pics. Plans have changed and I may be in the valley in a couple of weeks and I may be able to see it in person.
Satan does have a point. If it's just that, then a couple of turns to the hooks might do the trick. FWIW, my hooks have never come unscrewed on either of my 2 mustangs.
If you're talking about this one: http://www.latemodelrestoration.com/iwwida.pvx?;item?item_no=LRS-50648B%20%20%20%20%201&comp=LRS
then that's just the hook and isn't what I need, at least, not sure about you.
More detail please. What do you mean your valves are loose? Regarding pushrod length, did you swap out cams, if so you will need new pushrods, but the best way is to check.
:nono:
More back pressure will cause more heat and create more detonation. Like someone told me, try sticking a potato in your exhaust to see what backpressure does.