I asked a similar question not too long ago, we should talk about your goals for the engine itself.
Is it going to go into your C2500 or a different truck?
Are you building for street/strip use? Towing? Basic daily driving? Daily with a little extra?
Are the heads going to be the same TBI heads or are you replacing those as well?
Another thing to keep in mind, exactly which transmission are you using? NV3500? T56? Is it a fresh rebuild? Are you rebuilding it?
This information will help us find you a good setup, but don't be afraid to look into it on your own as well. The SBC is a platform that's been built a million times over, so plenty of builds available online for just about every single setup out there (but we're also happy to help out as well).
Happy modding!