buy this guys book and rebuild it yourself . he built the quadrajet for my gto.
i am not a carb guy so i had him build it for me. his book is supposed to be awesome. he has a 6 month waiting list to build a carb. really nice guy too. i well built quadra jet will give better fuel mileage than a holly. i have a holly 650 on my truck. it SUCKS as far as i am concerned.
http://www.cliffshighperformance.com/