if you want a 26 your better selling up and buying a gtr but if you'd like to go down the path of a 26 in yours with rwd setup easiest option is to buy a half cut as you'll have everything in there like all the hoses front brakes wiring resistor packs front mount intercooler+piping and yeh
same with the 25 get a half cut all is there like brakes, wiring and hoses and shit
cheers
andrew