Hi, I'm a chauffer driver/owner operator and also a car nut and am considering upgrading my current WN seies 1 (6.0 litre) to a newer LS3 powered WN Series 2...just because I want to own the last and greatest Caprice ever made. What are the differences between the GTS LS3 (325kw?) and the standard LS3 in the caprice? What would I need to do to the standard LS3 that comes in the WNII Caprice to make GTS type power? I also do Uber Black and Uber X and I'd get a kick out of picking people up in a "mobster" Caprice. Will cams and heads be involved or is just a matter of OTR, exhaust and tune? I'd also like to add the resonator as well for more interior sound. Is it possible to retrofit one to a caprice? I know I could just buy a Grange but they're very hard to find and very pricey still at this early stage. I just want to build my own surprising Caprice. Thanks.