The s1,s2,fst, saph and 3dr seats are the same mate the only difference is some have the release handle (s1,s2,3dr,fst) and the saph does'nt, in side the seats there all the same mate all the mounts for reclining are there there just not connected....all you need to worry about is the right subframes for your car..

back seats are a little different.. as the s2 is a 60/40 split a bit of modding would have to be made to fit the saph back seat but its easly done..both base and back rest would have to be modded from the saph to suit the s2