heater core replacement?

Well i have done this in 3 mustangs and it can be quite the p.i.t.a. If its not leaking I wouldnt try to replace it. You might get in there and mess something up that might put your car out of service for a few days. If its already leaking then replace it. You dont have to pull the dash completly out of the car. you have to losen both sides and pull the passanger side back out of the way. you must drop the steering column and remove the console to do this. The first one I did took me about 6 hours but the 2nd only took about 2 hours and the 3rd took 1 1/2 hours. I learned new tricks everytime I done it. Make sure you have some rtv to reseal the housing.

See http://home.netcom.com/~skent/mustang/1990/heater_core/hcore.html for some excellent how to do it help.

Check out my buddy's how-to article that he made when he did his heater core swap. Hope this helps: http://www.dork.com/hiflow50/heatercore_replacement.html

http://users2.ev1.net/~calley/Sally/heater_core/
This really helped me do mine for the first time. It took me about 3 hours. Be sure to buy a good heater core and not some cheap piece of crap. You only want to do this once, lol.