size/offset? and pipe size

[snookaholic26]

if im buyin a flowmaster super 44 for my 2003 s10 4.3, what size/offset do i get?? im just doin a single in single out muffler. no duels. just dont know what the offset should be on the muffler. inlet on the right, left, or middle? and same witht he outlet? anyone sure. again im gonna do just a single straight pipe. but im also wondering if i should just keep the stock exhaust or if i should go to a 2.5-3in pipe? i basically want the best sound. what do you guys think about a 3in pipe? to much?