as far as the windows go.... I would probably suggest that you get a new window motor regualator and stay away from the cheap ebay ones. Personally, I got mine from CarQuest and it works great, but I am not sure if they are a national or regional only chain. I have a TDC intake and love it......yes you will need to relocate your coolant bottle for any style of the FWI...... The dexcool can stay in there or go, it is up to you. If you stay with it you will have to change it out fairly often to make sure that it does not get acidic over time. If you swap it out make sure to rinse it several times because if dexcool mixes with any other type of coolant, it will form a corrosive type sludge which is obviously not good. I also have a two door 98 GTP. The window motors and regs are different from the two doors to four doors as far as I have read.........The coolant relocation part is actually just a standard gm issue part for the 99-03 models. If you want one, order it through your local dealer and it should be cheaper than getting it through a vendor(as I did) If you wanted to save more money you could look at junkyards, but obviously it wont be new then.