I would use a stand alone computer and run the 454 TBI just for the ease of driveability. It will start right up, fast idle, idle down after warm up and not vapor lock when pushed hard. There's also the availablity and economics of parts that are available most everywhere for the 454's over the Caddy engine.

There's my opinion, but I may be a bit biased. I'm putting an '89 TBI 454 in my 54 COE one of these days, LOL,
Scott

Scott Ward

2 1948 1.5-ton Loadmasters
The red one and The snow pusher
1 1950 3100
1 1955.1 Chevy 6500
1 1954 Chevy 6500 2-Ton
1 1955 1st Series COE 5700
1 1963 K20 (454)
1 1964 C10 (350)
1 1951 1.5-ton Dump Truck
1953 and a 1956 Ford F800

Raising a teenager is like trying to nail Jello to a tree!