Anyone got any nice easy ways to seal up the slip pipe on the MAC mids? Im getting a slight exhaust leak there and its slightly annoying.

 

Since it's already installed things are a little more difficult, probably better to pull the driver-side header. You need to dry fit the pipe until it just barely fits by slightly closing down the end of the socket. Light, evenly spaced tapping with a soft hammer or try to reduce it with a 1.75" T-bolt clamp. You don't need to completely seat the tube, just start it. Reinstall the header. Moderately coat the the last couple of inches of the tube with Permatex "Ultra Copper" high temp RTV silicone #101BR. (This is, by far, the best high-temp silicone sealant available! It doesn't seem to affect the O2 sensors either. They claim it to be sensor safe.) Install the tube immediately. The sealer also acts as a lube so the pipe should slide right in. Tighten the T-bolt clamp and let the sealer cure overnight.

 

I have the same headers. It was a poor design in my opinion. I went to autozone and bought a 1 5/8" band clamp, put the headers on loosely, then tightened up the band clamp and then tightened the header bolts. If you do decide to pull it and start over, be thankful its the driver side and not the passenger. good luck

 

MIG welder fix my problem fast.