Your engine builder's ideas are pretty good. If I was building that engine for that application I'd use the TF 240 heads and would not even consider the 270 heads. The intake choice could go either way. You already have the RPM manifold and it would work on your new engine but will kill a bit of top end power. The TF intake would be the best choice for power if you have room under the hood for it.

I'd put a hyd roller in an engine like that but you can make a solid flat tappet cam work if you're super careful selecting parts and breaking it in. With a hyd roller I'd stay in the high 230 or low 240 range for duration at 050. You do not want (or need) a lot of duration when using the TF heads. The TF heads flow a lot of air at low valve lift so too much duration will kill the power and make the engine run poorly on the street. You need to work with a pro when picking the cam for those heads. Your engine builder may or may not have any experience with the TF heads so talk it over with him. If you need another opinion talk with Dwayne at Porter Racing Heads. Dwayne can get you a custom grind that will match your combination and really make the car come alive.

For a true street car your engine builder is correct in choosing the Edelbrock carb but a Holley could be made to work if you pick the correct one. Personally I'd put a Holley Sniper on it. The Sniper adds a little bit of cost but you gain a built in data logger as well as complete computer control over the fuel curve and the ignition timing. I wouldn't build an engine like that with a carb but some people still do so it just depends what you're comfortable with.