Hello all, sorry it took so long for me to get the PM and get back to you on my install. It's been a couple years now sense I installed that Core in my Magic Air. I did cut the tubes back as much as possible and soldered the 90's on. I took a round file and elongated the tube holes towards the end of the housing. I wanted the tube end of the core to sit tight against the housing so there wouldn't be a lot of pressure on the tubes. Yes it was a tight fit, I just crammed it all together and have been using it without any problems sense that time. I wasn't super concerned with preservation of the heater housing as I haven't restored my 51 back to stock. It's my daily driver and I was only concerned with heat and having the defroster working. I imagine there are better options in core selections out there, but I spent $29.00 for that core and wasn't interested in spending more to have the end core (tank) installed off the old one. Had I been going to spend that kind of money I would have bought a Vintage Air unit and sold the Magic Air. Years ago Back in the 70's I cut the fins out of a 66 Bronco heater core and soldered the leaking tube up. It worked fine for the rest of the time I owned that 4X4. I would have done that to the 51 core but it was full of sludge.
Thanks for getting back with us, Rod. That certainly helps clear up some of the confusion. I'm still working on finding a solution that doesn't require modding the housing, but I've been busy with other things lately. All in good time!
Don't be afraid to take this heater apart. I have had a lot of this stuff, the 51 tubes and matching holes in the back of the housing that they go through, are farther apart than the 52 model. also the other posts have the photos of the 51 and 52 emblems correct, the 51 is lightly etched and filled in with paint, and the 52 is totally different and deeply embossed. If the tabs are broken off of the emblems there is a good fairly easy fix I have come up with for that. One other thing is that if you have a 51 and a 52 outside duct elbow in your hands, you will see that the difference is that the 52 elbow duct will have a flange that goes all the way through to the inside for the rubber duct connector to go on, and doesn't use the round backing plate with the round type inside metal flange like the 51. All can be seen in the Chassis part catalog pictures if you look closely. So the outside metal elbow ducts of course have different part numbers.
This was another good series of posts but again it does not appear ( unless I am missing something ) that a direct replacement motor was found, single speed motor yes but originally mine was dual speed which I would like to retain and the original motors ran in a CCW direction which will affect air flow.
Does anyone have any addit. info that might help with getting a correct motor?