Like Ken said I would go with the OEM replacement you may be saving $ now but there is a possibility it will come to bite you in the butt later. Also while you are in there you might as well replace the a/c evaporator (someone correct me if I'm wrong on the name of the part) since they have a tendency to go out as well. Good luck with it and let us know how it went.

 

If I ever have to tear down my dash again to replace the evap coil which I did not replace, the coil was still in mint shape. I would start researching on upgrading and improving the air flow coming out the vents. My passenger side vent is a joke. At high speed, it feels like medium low. My driver side, at high speed, it feels like medium high speed. I wonder if the air flow to the evap coil is too restrictive or the blower is not turning fast enough to really push air?

 

*Update 10-30-06*
The new heater core is now put in and the trucks heater is much better, seems like the heater blows out hotter heat than what it was before with the old heater core. The whole process of tear down and put together took about 3½ days to do but we took our time and did it slowly and tagged everything for where it needed to be for when we put the dash assembly back together. I haven't tested out the a/c yet cuz the only thing left to do now is add R-134a refigerant and put the facing of the dashboard back on then it'll be 100% complete. I hope this will be the 1st and last time for removing the dash, I don't want to go through that again.

 

builds character doesnt it... there are so many jobs I swore I'd never do again... one being the control arm bushings on my front end... now on my 3rd truck with the same setup so I know it's in the future [:@]