Technical 1951 Ford convertible frame question

Doing some rust repair and replacing body mounts and rubbers on a 1951 Ford Convertible. I know there are extra and different braces for the convertible and it also has the big X in the middle of the car. My question is about an extra 1/4" plate that has been welded on the bottom of the frame from the foot board back to the start of the kick up at the front connection of the rear springs. There is rust in between this plate and the bottom of the frame rail and a couple of broken welds. Is this plate factory? I feel like I need to take it off and get all the rust tended to but I don't know if I need to put it back on. No worries about if I can do it, but rather should I. I strive to do the best job for my customer and for the car without reaming the customer's checkbook. We aren't doing a frame off job, just getting rid of the rust, redoing brake, etc.

 

I have a 55 convertible and have read and seen pictures of that done on 55s and 56s but mine does not have it,it looks like it could have been done at the factory but I am sure someone knows for sure.

 

This one looks like it could be factory, but a really good fabricator could have done it as well.

 

Only problem is that there is rust inside of the frame also. You can clean it all up on the outside, prime it, use Por15, whatever... It will continue to rust from the inside out.

Sent from my Moto G Play using The H.A.M.B. mobile app

 

I recall that other manufacturers undertook similar modification to OEM convertible frames to strengthen them and minimise torsional twisting due to no roof. Use a cut off wheel on the welds and remove the entire strips before undertaking your repairs. When completed, seal with weld through paint and weld them back on in a similar manner to OEM. I would then squirt some light machine oil along both seams which will in turn seep into the space between the layers of metal (Capillary action).
Leave it for a while and maybe reapply again. Wait a while and then wipe off any excess seepage if you want to repaint the frame.

 

YES it is factory, not sure how much strength it added but it did come that way

 

My 51 hardtop had the same plate on the frame.

 

Thanks for all the answers. @mgtstumpy , that's about the plan I had without the oil. Never thought of that but it will be a good step. @Atomic Kustom, and @3quarter32 thanks for the verification that it is factory. I've worked on a '53 convertible that did not have that plate. I'll get it done up properly and I appreciate the information from everyone. viva la HAMB!

 

As stated above, Yes it’s factory. My 51 vert had it too.