Here is a pic of the inside of my 65' with a 67-68 radiator support:
I use a 24" wide 67' copper small block radiator.
To be up front, this is not a bolt-in affair. It requires welding and you must do a little modifying. of the new support. It was not a tough job, but you need to have access to a welder and some tools PLUS you need to have the required skills.
I installed the 67- 68' radiator core in a couple of afternoons. The engine compartments are the same height so that is not a problem. The top matches the front aprons perfectly, as does the bottom where the cross brace fits. The sides panels near the fenders are much different. I needed to remove some material from the driver's side near the fender and add some to the passenger's side. I also needed to cut out the hood bumper "triangles" and graft them to the new support. Perhaps the standard 67-68 ones would have worked, but I did not have any and none were included with the new core support.
Other area of concerns consist of what to do with the battery once a 24" radiator is installed. I wanted to retain the battery in the engine compartment and so I made a battery tray by combining the top pan from a 67' and using the under bracket of the 65'. I could have installed the 67' fender apron which incorporates the battery in a different location, instead.
To use the larger radiator also requires using the appropriate mounts. I bought the 67' type mount for the top and made the bottom mount out of some C channel and rubber.
In the end it would have been much easier to cut out the old support and install a different radiator, but I am please with the results.
I would just cut it and put in tabs. Seems easier. If you get a huge radiator, you have to make tabs anyway. Kinda becomes a moot point to cut and paste when you don't even use the radiator mounts
Just for fun I think I will put 65-66 shock towers in my '69--I really love the sexy curvey look of them. Has anyone done that?
Seriously though:
Dennis,
When I read the first post I thought 'what the heck is he trying to do and there is no way it will work'. But after seeing your picture, nice job. If I ever buy another early car, I may have to do that.
I keep telling myself that I am done playing with the early cars, but you never know!
I would just cut it and put in tabs. Seems easier. If you get a huge radiator, you have to make tabs anyway. Kinda becomes a moot point to cut and paste when you don't even use the radiator mounts
The 4 mounting tabs shown are not used. Those are for a stock 67-68 20" radiator. I should have cut them off, but haven't yet. The 24" radiator uses a factory bracket off the top of the support. You can see the 2 elongated holes in above pic of the radiator support.
Once installed, the radiator looks totally stock, which was my goal in keeping with the "sleeper" theme.
The bottom mounts were home made (have orange rubber in them), but the 67-68 factory ones could have been used instead.
Anyways, the purpose of my post was to show that the newer radiator support can be installed, without too much work, if one desires a factory look with a 24" wide radiator.
nice jod dennis, but far more work than i would be willing to do, unless the rad support needed to be replaced anyway. i would cut the larger opening, modify the battery tray, and build a square tube frame to mount the radiator to, as well as add back strength that you lose when cutting away the bends in the core support.