Code on firewall

[spinshop]

Did you check here?
After looking back at this again , I think the stamp on my quarter is 5837? I will check.
I think what might have happened is they used a standard Chevelle 2 door sedan firewall (5411) instead of a Chevelle Malibu SS. (5837)

1964 Chevelle Miscellaneous Information

Decoding Chevrolet VIN, trim tags, cowl tags, engine, engine block casting numbers, cylinder head casting numbers, intake manifold casting numbers, transmission, interior codes, and paint codes.

chevellestuff.net

 

[Nashville Cat]

At least we know what the "5411" on the firewall means. The Z38 is some kind of sub-assembly ?

 

[spinshop]

Well, I checked the stamp on my quarter panel last night and it`s been painted over too.
I`m pretty sure they were the model number.

 

[cheveslakr]

The quarters varied from model to model, but sometimes only the piercings for trim not necessarily the shape......so that stamp represents body style and date. My '69 two door post sedan has 13427 stamped in it, since it didn't receive the astro ventilation door jamb vent that malibu based cars did. The '64 SS got the upper quarter panel trim while the malibu got the mid level trim, so they are different.
Just thought of this, but '69 malibu received trim molding between the door and the rear wheel opening, but the SS396 and COPO cars didn't. This was made possible by not having 2 seperate quarter panel stampings, but having a stud welder simply add them on the assembly line, then drill a self tapping screw inside the door jamb to attach the forward most tab. This system also aloowed the quarter panels to be pulled from the same stack. The SS396 became an option in '69, not a seperate body style, so this muddies the waters a bit. One thing that intrigues myself and many others is knowing the EXACT methods of original construction, line techniques, sequencing, outsourcing of components and chronological finishing techniques, paint and plating. Since records and line videos are scarce, original unmolested example cars are invaluable in the education. Another reason why restored cars are overlooked sometimes in favor of survivor cars.

 

[spinshop]

That`s kind of why I believe his firewall panel was just a mistake on the assy line. Or maybe not a mistake, because there probably isn't much of difference between them.
I might just sand mine down to see what the number is. I`m 90% sure it was the SS model number. I`m curious to know what the other numbers are for also.

 

[cheveslakr]

Not a mistake, the model code stampings were across the various lines, but always started with the entry level and changed accordingly. If the panel didn't vary between models, the code didn't either. No reason to have multiple numbers on the same piece. Much like a 1966 chev pu rear light having a '60 date code.......the light was first introduced in '60 and unchanged till '66. That confused a lot of kids thinking we were so smart to peak at the light to identify model year.
If you're wondering why a part even had a model code stamped in it when they never changed per model, I'd offer the theory that the gang stamp was used for various parts and the holder had to have all digits present, so they scrolled to the lowest model designator and had at it.