Hot Rods Edelbrock C4B, C3B and C3BX

My C4B looks to be the "passenger-side" variant with uneven runners and without coil bosses.



My C3BX appears to be identical to @Moriarity 's sporting driver's side fill, uneven runners and coil bosses. No 3bbl cutout though....



Both, unlike @Moriarity 's and others, are filthy and unused! Need to fix both!

 

I think Edelbrock reused the C4B molds for some of the new C3B's, they didn't have to change much though just the Carb mount & Intake opening, which gave them there new C3B (this is just my opinion) The big changes came to the C3BX.
The front Oil Tube was changed from left to right & middle, I think it's bcuz of the different Chevrolet Vehicle's, the Radiators Top Coolant Hose came in different angles, some had open other's closed PCV systems, different Caps on the Oil Fill Tube, some had Closed Caps, other's had Oil Fill Tube's with the Big Open Breather Cap.
Some of the C3B's & C3BX's had the two threaded mounting bosses next two the Carb on the driverside, maybe for a EGR bracket or Carburetor Linkage Bracket, I'm not sure what they were used for, maybe y'all might know??

 

^^^^
I always thought the bosses on the drivers side of the carb were for the big AC compressor bracket from the 70s. My C3BX has them.

Gary