Yesterday, I made the reproduction core support functional in a '66 2wd F100. This question comes up a lot, so Here's how I did it (taken from my blog):

I got a chance to get a little work done Sunday on the pickup. There is no core support reproduced for the 65-66 2wd F100 pickups, but it doesn't take too long to make the 61-64 reproduction work.

The primary difference between the 61-64 and the 65-66 is the lack of support brackets for the inner fenders on the earlier trucks. Then, Ford changed the radiator mounts for 1966. Do what you want with the radiator support brackets. If they stay, buy a 65 radiator. Remove them and buy a 66 radiator.
First, to make it fit, you have to remove this bracket shown below:

It should be stubbier like this one:

If you are using this and want to keep the 65 style radiator mounts, you'll have to keep the original bracket and swap it over.

Then, I drilled out the spot welds holding the inner fender bracket to the original support. Usually, these are good enough to reuse. If it's really bad, it wouldn't take much to fabricate them out of some angled steel using the original as a pattern.

Next, I had to mock up the front end to find correct placement of the inner fenders:


I took an awl and scratched deep into the core support so that after removing the black primer from the support for welding, I'd still be able to find it.

I used a cupped wire wheel to clean off the primer and shot it with weld through primer.

Then, using the holes made for cleaning off the spot welds, I plug welded the brackets to the support.


You can see in that picture above that I have completely removed the 65 style radiator mount leaving holes where I drilled out the spot welds. I'll fill them in with the MIG for a finished final installation.
For my time and money, it's a lot better to replace a panel than to stitch a rusty old core support back together or pay a mint for a rust-free original only to find out it is rusty. I'm going to have the support blasted clean of the EDP to match the rest of the metal for finishing.

 

Great timing. I plan on doing the same thing soon and it is nice to see pics of someones work to know I am on the right track. Thanks for taking the time to write it up and post pics.

 

This is a great tech article; hopefully someone will archive this for future use!
thanks for the info.

 

It doesn't take too long to do. If I had it to do over, I'd probably mock up the entire front end to guarantee as much as possible that the brackets end up where they should be. I don't think that it's too critical though since these trucks were designed to be assembled quickly in the 1960s which was probably before drug testing in factories.

 

Thanks for the informative way you step by step explained your swap.
Read and hopefully took it all in, I had been thinking of fabricating the inner supports but had been wondering about the radiator frame, the battery is being moved rearwards so the tray is not an issue as I want to conceal what little wiring there is as best I can.
I also plan on fitting air before next summer, but that another issue that will be dealt with in time.
Thanks again.
Oz66

 

I am restoring a 66 2wd f100 stepside. I have looked high and low and this article from bluestang65 is the best and least confusing I have found. I am doing the exact same repair with a 61-64 radiator support from LMC.

 

Bluestang65, with this being an old thread; at the time you bought the core support that you did this mod to, was there a core support being reproduced that had inner fender supports?

 

No. The 61-64 was the only core on the market.

 

I see. Now there's a support for a `65 4WD, would you have used this instead if it was available? I'm really undecided on which of the 2 reproduced supports that I should go with if I choose to buy new. I guess the `65 has fender supports already on it. I believe the radiator brackets are different and would have to be changed regardless so with that being the case the `65 support looks like a likely choice. I just wonder if the battery tray is different on the 4WD?

 

There is only one support on the market. The 65 4wd uses the the same inner fenders and core support as the 61-64 2wd and 4wd.

 

Actually LMC now offers 2 core supports. The first one is the 61-64 2wd/61-66 4wd (LMC p/n 43-2855) that everyone knows about. They now offer a second core support for 65 2wd (LMC p/n 43-2857) so I am guessing that the difference is the way the radiator mounts as was mentioned in the instructions on converting the old core support to the 66 radiator mounting.

Mark

 

I will have to drive over there and take a look at it. Using it in a 66 would only require also using the 65 style radiator.

 

That's what I'm hoping. If you find out about it please pass along your findings.

 

if using a 65 coresupport in a 66 you can also have the mounting brackets on the 66 radiator taken off and turned around and switched to the opposite side any good radiator shop can do this ive done this a couple of times on my trucks

 

Just curious if bluestang has checked out the 65 to see if it was a better support? Looking to do the front end soon and would be thrilled if I could use the 65 support and only need to swap the radiator.
Thanks