Bill,
I tried to post some pics on the same location that you did for yours, but haven't got it figured out yet. My pics are posted at the site, but don't know how to get it set up like yours, where you just click on the blue description. I need more experience with that, I haven't done the link thing before. I will try and get that updated.
I did check my '58 frame today, and it does have the radiator brackets located 3-1/2" CL of rivet to CL of rivet like you referenced before. I don't know what the factory V-8 mounts look like for the '58 (the guy told me the mounts were for V-8), but if they are, why are the radiator support brackets riveted on, wouldn't they be bolted on from the factory? I will try to put some more pictures on the opera site under a different album that show details of what I am talking about.
Here are some discrepancies I found today. My '58 radiator support brackets are located 3-1/2" from the main crossmember, but the bracket attaching rivets are 6" OC, rather than the 5" OC of my '55.
My '58 core support brackets are 18-1/2" CL to CL to 1/2" reference holes located on top of the frame. My '55 core support brackets are 17-1/2" CL to CL to the 1/2" reference hole. There is the 1" difference I am coming up with. I am lost as to what to set the core support dimension to. If anyone has there frames available to measure, it would be great to set what everyone else is coming up with.
Last edited by Oleblue55; 01/02/2009 10:33 PM.