[stuck]

I think I would look at the miles first....miles affect everything...not just the motor...., but the ball joints, bushings, rear end, bearings....everything.

I replaced every servicable part on my donor parts (ie bushings, seals, bearings...needless to say, I went non donor! But I went the IRS and carbed route also, so non donor makes a lot of sense in that case.

If you are looking to pull it out of the mustang and drop it into the cobra....miles is all you'll care about IMHO. If its got some goodies on it, then great...but all that little stuff that wears out gets expensive.....

Good luck....