Since both the intake are so similar, it’s really a price vs originality decision. I was in the same boat 3 years ago and found a LD4B for $140 shipped. It had been installed new on a boat in the early 80’s that only had 140 hours on it. It just needed a wash before before I spray bombed it blue and installed it.
I like your setup as it’s exactly what I did (318 with a mild cam, 302 heads, 340 exhaust manifolds and a 1406). Being a ‘75 it’s already got an electronic ignition but I did install a distributor from Trailbeast to get rid of the slow curve the original ‘75 distributor had.
