Still trying to wrap my head around this. Your single 76 has a claimed approx. 400 hp left in it, but you want to upgrade so that you can make 50 more HP than what you do now, because you want to stay at the same boost level? Does your class have some boost limit, or am I not getting it? Things do get by me sometimes!
My point is this. He asked about a cam. What to many people call a "turbo cam" can be good or bad for a turbo engine. An under turbo'ed combo will work fine with that style cam. Put two of those turbos on there, and the cam specs that will work with over turbo'ed engines will have specs way closer to a "N/A" cam with better results.
Trust me, I understand. The power undersized turbos will make on a car feels great... But after you put "proper" sized turbos, You will recognize the "choked" term I use.