Thanks Curtis! Jerry was nice enough to give me a response, which is paraphrased below:

Quote
I am afraid you do have to discharge the AC system to remove the heater assy.

It is possible to get the heater box out but you have to be real careful not to crack the lines moving the evaporator around.

... It is much easier to just replace the heater box assy that to just replace the core, because you have to take the heater box apart to get the core after you get the box out of the truck. And the diff in cost is only about $30 or so. A new box has all the control levers and diverter doors already installed and the core is a heavier duty unit. It usually takes about 4 hours to do the entire job.


I have the new style heater boxes, they run $305.00 plus postage ...


I can get a core by itself (not sure if it's rebuilt or new) from rockauto.com for just a little over $100.00. And while this might take Jerry just 4 hours ro so, it would probably take me a weekend.

Some of the rockauto.com cores look like they may be metal and not have the plastic on top, though I am just guessting from the drawing.

Anyone have any insight on that?

'94 HONDA Passport (very similar to the Rodeo -- too similar for mere coincidence!!!)
DOR lift, 3" Body lift, 33" BFG M/Ts, Receiver mounted winch, ARB rear air locker, Tera Flex Low, Garmin Emap GPS, FRS/CB radio, as many toys as I can find!