Well with that "mild head work" you're probably not seeing any power gains due to the stock carb not flowing a whole lot of air, also, if you're running a stock intake. My car still has the stock intake and carb, but i 'think' the carb has had the jets sized up or something because it just runs like a bat out of hell....it's probably the best tuned carb i've ever driven (i wish i had tuned it...previous owner)
Anyways, i'd say hell yea it'll make a difference, especially if you get a matching intake to go along with it. If you've got the cash to spend, i'm planning on getting an RPM Air Gap intake since it's about the best duel plane intake on the market, and a BG 650 Speed Demon carb. Even if the carb flows a bit more gas than i need, just get a FP regulator and be done with it.
I priced the intake at my local speed shop for about $239.00 which is what most of the mail order places want. I havent got a price on the carb yet but those Speed Demons are a work of art...Plus unless you plan on building the hell out of your motor, it'll probably be the last carb you ever buy. If you're planning on a stroker kit or something in the future, buy a 700-750 and regulate the fuel pressure down so it doesnt run rich, then you'll have your extra fuel in the future when the need comes.