Carburetor size Question

I have a 318 getting finished up and will be needing to upgrade my carb. Currently the engine is a stock 318 HD in a 1976 D100 that was ordered for Cal Trans. It has a 360 intake on it and I've always been curious if the HD designation had it built with 360 heads and intake in 1976 or if these were add-ons. The engine had reportedly had the oil pump replaced by the previous owner. After a few months of ownership and the truck running like **** I was tuning on it and decided to buy an Edelbrock AVS 500 cfm carb to use on the current engine. It ran much better with this carb.
The good times didn't last as it started knocking pretty bad and parformance dropped off so bad that I could barely get up the hill on my driveway. With the report of a previous oil pump replacement I decided to just have a different 318 built with a '73 340 cast crank I had laying around. Around this time Speedmaster was having one of their salse so I got a pair of bare heads and an air gap intake.
Specs on the new engine are .060" + for "328 cu in.", '73 cast 340 crank, Eagle SIR rods, KB167 pistons, GJ oiling mods, HFT 224/230 @.050 lift on a 110* LSA, Competition Camshafts adj. rockers, bowl blend on the SM heads and gasket matched intake. I am thinking about an FBO ready to run distributor. Fresh 727 with mild work, the shifts are a little firmer but nothing crazy that is annoying for street cruising. Stock converter, 3.23 gears. This is just a SWB, parts chasin'/run around town "sport truck".
Any ideas on HP and the main question of what carb? I really like the AVS. I was flirting with doing a Fi-Tech but leaning toward sticking with the AVS style since I was liking it in the 500 cfm form with the 318.