I think your model is considered as a standard model, so it may came with standard height springs (as you found out). According to your OP, the new shock has helped the springs to bring the car to its proper road height. I think regardless of make any replacement shocks may do the same thing.
Plus, when you changed to the 17 inch wheels from the 16 inch wheels, you have increased the height by that 1 inch or so. As you have already researched, you can use lowering springs or spring perch drop units (usually used a the front) to get it back to the height you desire. This is your best bet.
Changing the bump stop does absolutely nothing to lower the car except to increase wheel travel, which can be a good thing in certain circumstance.
Good luck and keep us informed.
Name: Blanca | 07 E92 | AW-Blk | ZSP | Alcon BBK | M3 Bits | VM RR Links | Koni | UUC Sways | V5 | Dinan CAI | ETS IC | Fge DV | ER CP | Cyba | Raden. Exh | Mod Step | Trunk Drawer | Perf LED Wheel | Illum Dr Sills | IS Shifter | Parrot | Philps D1S | 6000k fog | MTECH RR | CSL Trunk | Aero | Roof Spoiler | PSS on BBS RS-GT 19s
Last edited by Thumperx; 01-01-2012 at 12:31 PM.