Take the MAF off and you won't need to do anything, unless you want to bump the timing. Other than that you won't make any less power with the stock maf.
Yeah, I agree with jstreet.....if upgrades are in the future, the the 75mm T/B is fine, but you're going to have to go a long way with N/A mods before you peg the stock 80mm MAF unit.
You can flow something like 70% more air than a stocker requires with the stock MAF which is already 80mm. If you think about it, that's about the typical size people put on a 5.0 with a 75mm TB.