<E30> Springs for Bilstein HD's

[Dreamsound@xxxxxxx]

Which performance spring option would be best for my '91 318is?
A smooth, non-jarring highway ride is a must, it's my daily ride.
I'm currently considering:

Used E30 M3 springs (please e-mail if you have some FS)
Bavarian Autosport
Eibach Pro-kit
H&R

I'm asking because I just put Bilstein HD's on the car and afterward I found 
out from Bilstein that they're only designed for the M3; they don't make them 
for the other E30's.  The shocks do not function properly with the taller, 
softer 318is springs.  Therefore I need M3 springs, or something else that is 
lower and slightly stiffer.
Thanks,
Mike Crotty
1991 318is

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