Alright so what i understand with the SD headers, ill need new gaskets (front-back-down pipe catback)?
New clamps? or use the same clamps and seal them up with RTV?
and i got lost with the down pipe part... I need to get a custom one? what do i have to do exactly? and whats the size 2.5''?

those?
http://www.ebay.com/itm/97-08-GRAND-...item3a7118c532

or those?
http://www.ebay.com/itm/97-03-04-08-...item2c634a220d