Easiest / Hassle free method - go with Driftworks adjustable sliding rails or Apex's version, both designed for Side mounts and both will get you on your way easy enough. Although, if you have a super wide seat or a GT seat, then most likely neither rail will be suitable and you'll probably have to go custom. Otherwise, its just a case of bolting them in really. The major difference between the two from what I recall, is that Driftworks (£150) rail is single locking whilst Apex is double locking (£100) Check out DW shop or Apex performance.
