Re: new alloy help please
Welcome to the forum rich.
Those wheels should fit but they may not fill the flared S3 arches as much as you'd like. I believe the offset of the standard alloys (7.5 x 17 Avus) is et32. I'm running 18" RSTT alloys (8 x 18) which have an offset of et33 and i dont think they stick out enough.
Regarding the spacers, have a look at THIS thread.
Out of interest, where are you getting the forge spacers from as i'm looking to get some as well.