Is this the system?
Looking at it in pictures, looks like a nice system. Looks to be well laid out. The fact that it is larger in diameter than stock means that clearances are going to be tight. If I had purchased it, it would be with the expectation that I may have to tweak it here or there.
I would have started by verifying that everything fit together on the ground, before trying to fight anything in the air. Based on the portions that get clamped and the fact that they fit inside each other, I'd have lubricated each connection to allow for easier rotation as well as removal if need be. And dents at any of these areas may mean a slightly oblong hole and thus a trickier install. For that, a file and possibly a belt sander.
Once installed, again, verify potential contact points. A mini sledge and a socket extension work well to tweak as well as a pipe or large prybar to gain additional clearance. Nothing gets clamped or clamped tightly until I'm satisfied there is enough room.
I've installed a number of systems on a number of cars and trucks as well. Trucks are a bit too easy because there is always plenty of room. My experience with exhaust systems on the S197 (and I have a bit of that too) has been that it can be tight at certain points along the tailpipes. Panhard bar clearance, having installed a few of Maximum's panhard bars/brackets on Fox chassis cars, is almost always an area to pay extra attention to. Especially when installing oversize diameter tubing.
I wouldn't expect most to go as far but I have no issue using a sawzall, cutoff wheel in a 4" grinder, or firing up the MIG (let alone the TIG) to address an issue. Then again, I aim low with respect to expectations of others and their work, always hoping to be pleasantly surprised. Having to do extra work to ensure that things are done the way that I want them seems to be the norm as far as I see it. I'm a tradesman too.
Very well said, and that's exactly how we do it as well. People don't think to lube up the exhaust and it makes it a ton easier to get the fitment correct.
I had a mail order customer buy this system from me. Similar scenario (not saying this system didn't have issues), but the customer said there were issues with the system, went back and forth with pictures several times.
He ended up taking it to a local to him exhaust shop. 1 1/2 hours later he was driving with perfect fit.