Im eliminating the ac from the truck while I have the dash apart. I also would like to eliminate the hvac system, but still need heat for the winter. I was thinking of getting a diffrent heater box from some other vehicle and putting a diffrent blower motor in there, and making my own ducting. Anyone have an idea?

 

Indy,
Not too sure on this as I've never done anything like this on one of our Rams, but I would suggest looking for a foreign car (Toyo., Nissan, etc) with HEAT ONLY. That would have a small enough HVAC box to let you position it just about anywhere under the cavernous dash of these trucks as long as the core tubes line up with the firewall holes. That may need some extra hosing to accomplish, or you could just re-drill. You may also have to go to a cable type activation system. Or just leave it so that it is OFF all the time or ON all the time (no blend, vent, or other fancies)
That having been said...Yes, it COULD be done...but not too easily. Unless you have nothing but time and like to tinker.

It may be easier to just remove the a/c evap. and leave everything else. OR mount a heater core in a homemade box and open or close it with a cable lever.
Also, if you do something like this, use a heater control valve to shut off the flow when not needed, i.e. SUMMER!

 

I'm with Wayne, just remove the evap coil and re install the OEM heater box. The box is mostly plastic and doesn't weigh that much.

 

This is the first time im laying eyes on the hvac system. I really have no clue how it all works. I NEED to replace the heater core. It just looked to me that to replace part of it I have to replace all of it, which is why I wanted to retrofit. Yall say I can just redo parts of it, so I guess Ill just have to investigate harder. While were on the subject...do you have to remove the whole hvac unit to replace the heater core and replace the box surrounding the core? I should really just take a picture to show what needs to be replaced.

 

Well, the HVAC box has to come out of the truck to get it apart. It is in two pieces and the heater core and evap are sandwiched inside as are the various plenum doors.
Some one the forum have just rocked the dash forward and squirmmed the box out, but I find it alot easier (with a helper) to remove the dash from the vehicle.

 

Read the DIY on the heater core replacement.