exhaust manafolds

i have the 96 caprice w/LT-1 motor and will be doing a LT-4 conversion on the top but first want to get rid of the stock exhaust. any ideas on a good exhaust manafold? any ideas on free flowing cats, willing to use oxygen sensor simulators if a code was to be set. i see hooker,elelbroke have a set simalar in price, then i see borla has a set. i'd like to hook these up to the stock 2¼ stainless steel pipes with flowmaster 50 series mufflers and later upgrade to 2½ pipes. has anyone done anywork in this area.
thanks

go to www.clearimageautomotive.com. They have a set of tubular manifolds that make about 20 more horsepower on a stock engine. The tubular manifolds fit good and have great spark plug clearance.

thanks, that seems what i've been hearing from a couple of other forums.