I must have missed something along the way. Brian, why would you think about changing out an original correct frame bracket for an incorrect one just to be able to use original insulators, that would also be incorrect (not correct stamping on the rubber), versus using a set of repro insulators that are just like the originals with the exception of no rubber “C7ZA” stamping ? In either case, neither would be Factory correct. The aftermarket/ reproduction insulators are reasonably priced, and available from most suppliers for less than $20 each.
I believe that all of my Retractable and T-Bird friends over the last 35 years, as well as John here, will agree that I am kind of a “stickler” when it comes to originality, whether it be major parts or down to the smallest piece of hardware, and whether it shows or not. However, using an almost 50 year old rubber insulator, particularly if cracks can be seen, is, in my opinion, a safety issue; something like still wanting to use an original camshaft or brake shoe, even though they are worn, just because they are original. If the insulator looks like the original, how many people are going to go under to see if the rubber has the correct “C7ZA” extrusion cast into it ? Back in the 70’s, I actually had an original insulator on my ’57 Retractable have the rubber come unbonded from the steel part. While it was a little scary when it happened (I was driving it at the time), it was more frustrating having to replace it after the car was complete. I “kicked myself” for not replacing them when I redid the engine.
Enough of my “soapbox” talking. Back to the issue at hand.
Scott : on the insulator that you provided the picture of, is the “C7ZA – E” extruded on the rubber, or is it paint stamped ? The reason I ask is because that sometimes, when Ford phased out a part and replaced it with another “that would work” (although not be exactly like the one it replaced), they stamped the number on it. If in fact it is extruded on the rubber, and thus definitely an “E”, does anyone really think that tolerances were so close that ¼´would make a difference in something rubbing or having a clearance problem ? Just throwing that out for comments.
Bottom line, IMO, if you are planning on driving your car, I would opt for the new rubber reproduction/aftermarket insulators. However, that being said, I think it would still be beneficial to have more data on dimensions of “E’s” versus “F’s”.
Bob