I'd recommend Fernando at Transmission Physicians on Crenshaw Road. I'd recommend doing research on Camaroz28.com.

If your on a budget then a LT4 383 is not the way to go. You say you know what your doing, "for the most part" but I don't think you do because your asking about what kind of intake is best for the LT4.... well all there is an LT4 intake, no improved aftermarkets except for sheet metal intakes which are over $1000. Even edelbrock aftermarket ones you see are the exact same as stock.

You should ask these techs you've been talking to how much a "cheap" LT4 383 would cost. And you'll probably find its not so cheap. And when your looking for cheap parts like your doing, you'll probably end up spending more money because you don't know what you need or additional costs that go along with it.

I'd be looking at putting that money into making sure your car runs right, repair all the worn parts, and doing exhaust mods, and intake mods..