I was unaware that such a wide variety of spindles and joints were available for the M2 based components. I have never seen any mention of the availability of alternate components offered through the variety of coil over kit suppliers, so never knew they existed. Since I don't play in the coil over world, I've never had any reason to look up if they existed either. This availability obviously changes what can be adjusted in the aftermarket system and opens up new possibilities. IMO, the original system is similarly adjustable, but it is not as easily accomplished, and yes, this would include control arms of varying length to alter track width. Since all the racing I've done has been severely rule restricted, I've always found ways to make "stock" parts work for the application to avoid the penalty of using obviously aftermarket parts.

If they offer it, I would suggest having Gerst build your system with a splined sway bar mounting system instead of an off the shelf bar. This would allow almost infinite bar tuning options. I suspect you may be looking at some soft spring, big bar combinations with the variety of springs you are chasing down. The ability to change the sway bar to balance the roll couple percentages would go hand in hand with spring changes.