The dual 2bbl progressive 32/36 type setup sounds workable for the log manifold six. The versatile progressive 2 bbl 32/36 would likely tune easier than three
progressive 1bbls. Weber JEts are accessible, running
synchronous would have small primaries and 32/36 has built-in
progressive secondaries!. Adding two ports for the carbs on the log runner without too much height is a concern, 'Thinking of slicing the intake runner log and adding a plenum box to the outside of runner for enabling carbs. The Carter 2bbls CFM's compared to available 32/36 ?, Are jets available ?
I've ran a single 32/36typre H/W 5200 on a 63/170 Falcon, also tri-power 3X1 Holley 1Bbl's on the 250/ '61Comet. I tried a plenum on tri=ports with one big 2bbl on the 250 for simpler tuning. Plenum 500CFM 2Bbl idled consistently and ran smoother than the primitive 1904 1bbl's,
but wasn't any faster.
.
Impressed with the progressive 2bbl, considered
one 32/36 inside a plenum with a compressor :
I found a U-Tube video of a nice dual 32/36 setup : (if link works?)
https://www.youtube.com/watch?v=BfTqONGkJl8
habe fun