Installing aftermarket radiator, I should have expected this

[MountainGoat1966]

My OEM 31 year old 2 core copper/brass radiator in my 84 K-10 is not flowing worth a darn and the engine runs shall I say, a tad warm .......
I don't want to burn up my stroker engine I built many years ago, so ..... here goes.

It's 130 miles round trip to a radiator shop, and they will take all day to do a rod out and test, so I bought a 2 row aluminum/plastic from O'reilly's.
I know the aluminum will dissipate heat better than the copper/brass, but won't last me another 30 years or so.

I do plan to have my OEM one cleaned and will stash it in the shed since the tanks and core are still in excellent shape, just the cores are plugged up.

The problem comes in when I try to install the upper mounts.
Because of the design and manufacture of the aluminum radiator, the mounts will not work.

I MIGHT be able to cut and modify the mounts with a slot for the radiator seam, and slide a piece of old rubber inner tube or something in there to help cushion it, and use a couple flat washers under the bracket so it bolts tight and not at a funny angle.

Has anybody ever had to do this project, and if so, what was your solution?

Also, since my heater hoses both connect to the engine, I won't be using the hose fitting on the radiator for the 3/4" return hose, and from looking at the new radiator, I sure don't trust that goofy plug with hose clamp they supplied.

I would like to keep my original mounts intact in case I need to reinstall my original radiator, and stash them in the shed also (in a safe place where they won't sprout legs and walk away).

Gotta love these old trucks at times ............ I only have two of them, and the only thing keeping me from buying more old Chevys is a lack of funds.