I am replacing the heater core in my 90GT with A/C, I've got the old one out and the cover off with the A/C still connected. The cover plate won't go back on properly now, I know if I unhook the A/C I can pull the housing in further and get it back on But I'd prefer not to do that. I am thinking about cutting the cover in half so I can bolt the back half in and then install the heater core, and then seal the cut with some tape. I'm thinking that if I do this and I ever have to replace the heater core again it would keep me from needing to pull the housing out at all, just pull the 2 front screws and front half of cover and be able to swap the core out. Any thoughts on this? I have a Motorcraft Heater core, didn't go with a cheap replacement core because of how much of a P.I.T.A. this job is and plan on keeping the car forever, had it 26 years so far. I might try just cutting the sides to see if I can bend it up enough to get the core in, just so it isn't cut completely in half.