X pipe installation problems

After reading a post in this forum I decided to put on an x pipe from Pacifica. Cheap, easy to install except for: The stock studs have a shoulder on them that will not allow you to tighten up enough to avoid leaks. After searching the forum in this venue and others I find that I am not the first to discover this. So I take out the stockers with vice grips, easy really, imagine doing this on a 10 year old fox car, and simply use a bolt equivalent since I could not find studs. I tried to explain this to Dan of Pacifica, a MAC offspring, but he basically called me a liar and I then said, "Read the Mustang bulletin boards". I do not have clue about any power gains but it sounds mean as hell. I used my old MIL eliminators, had to cut the locating tabs off of the O2 sensors. I should also mention that the forward drivers side O2 sensor plug is a bitch to unlock, there is not alot of slack in the factory harness.
Man, you just got to love the aftermarket suppliers, don't you.