Well mine is a 69, not a 68, but I THINK that A/C big blocks had the duel snorkel air cleaners(68/69 B-body) ...........
I was told on a different site that 68/69 big block A/C, 4Bbl cars all got Holley carbs.
too much wrong info/thinking in this one post .....
B-rad, you'd be best to start your own thread giving specifics of your car and the questions you have.
1969 383HP 4bbl
originally used Carter AVS carbs
ONLY 1969 383 4bbl used HOLLEY carbs with and without A/C
1969 383 4bbl & 383HP 4bbl both
originally used dual exhaust manifolds (as pictured below)