I went with the Edlebrock Performer kit/package (cam, intake, carb) on my 69 Impala, 454. I am very pleased with the performance of the engine with this package. Besides lots of HP, the 454 achieved 17mpg on a 2000 mile round trip to the Black Hills in South Dakota (cruise mode). This thing will go down the highway at 70 mph with hardly any throttle. 2.56 gears help. The only problem I'm having with the motor is that it seems to have too much ignition advance (pinging problem), and Roy has been helping with this (may be one of the reasons I got 17 mpg).
This is my second Edlebrock Performer kit/package that I've used. This first was on my 72 Rally Nova, 383. Had good experience there too, with one exception. The performer intake had a flaw in the casting where the coolant temp gage sender is screwed in (a crack). I managed to file out the crack and still have enough remaining threads for the temp sender. Good luck with your project