Four barrel carburetor for slant 6 Offenhauser manifold?

Bewy said
If you have a 4bbl Carter, you already have the best carb.....

Hello Bewy,
the tag on the Carter is 4299S 6-1771. The secondary's are stuck closed and I wanted to try and free them up before I start carb shopping. Thank you for your input.

Bewy said
The 4299 is off a 67 383 Auto Trans & has 1 7/16" pri.
#404 rods. This is a three step rod, 063/060/051. Should have domed piston covers, not flat.
0.089" Pri jets
# 368 sec jets which probably have a 0.068" orifice.

To free up the shaft. Heat alum with a gun around the shaft area. Dribble in some ATF while warm; gently try to move shaft, not excessive force, or you could twist the shaft.

Thanks! I will try a little heat/atf and wiggle today and try to get the shaft loose.