The air box and the evaporator are different in the SBC and BBC Camaro. The box and evap look similar in the BBC box and the box in 1st gen Firebirds. I hunted for both at swap meets forever but came up dry.
On another note I did finally find a BBC in cab heater box and heater core but need the correct engine bay heater box cover. Thus my original post.

HeartBeat City sells this 67-69 Camaro Big Block Heater Cover
https://www.heartbeatcitycamaro.com/...54-Without-AC/

Is this accepted at the LEGENDS judging Level ?????

As I have the #27 ZL1 OEM/GM Heater Box that I'd like some comment on !!!!!!!!!!!!

Id sure like to see a small block and a big block heater cover side by side. Id also like to see a high resolution picture of the cover you have. There's a NOS BBC cover for sale on EBAY right now but I couldn't make a comparison from it to the HBC repop. Off topic, the BBC Summit brand heater core is actually smaller than a GM heater core and actually fits in the SBC interior heater box.

If you go to all my posts on page 20 there is a picture of a bb heater cover i sold

I heard a statistic that it cost $20,000 just to pull and maintain the part number in the engineering release system.

That doesn't count designing, validating and tooling the corresponding part.

GM was not super concerned about saving money back in those days.

K

Don't forget the heater hose plugs

https://i.postimg.cc/LX4zTMXw/heater-core-plugs-001.jpg

https://i.postimg.cc/Wbz5V0sC/heater-core-plugs-002.jpg

I used a small block cover to replace my damaged original big block cover. I put them side by side and couldn't see any difference. There are dimples on the small block cover where the holes are pierced for the big block hoses, so all I had to do was drill holes.

Pictured is the OEM/GM Big Block Heater Box removed from the #27 ZL1 Camaro at some point when it was raced by Dick Tutino, Service Mgr at Seattle's Alan Green Chevrolet...

This box does not have the rectangular flat area as is shown in post #1 of of this thread.......
Could someone explain ????

Is there much value to my OEM/Original Heater "box" versus the $70 repro that
Ive seen on Heartbeat City web site ???