Spacers won't help you in the front, hate to say it but it probably has more to do with the actual wheel specs and sizing So ideally you'll need to convert to studs and.
Could moving the current front wheels to the back and vice versa fix the. Someone else mentioned it but you have to consider our cars don't use studs like most Complete bmw wheel spacer guide
ECS News - BMW E46 M3 ECS Wheel Spacers
Choose the size spacer closest to that measurement without going over
RennMotorsport 5x120 Wheel Spacers with Extended Lug Bolt fit BMW E46
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ECS News - BMW E46 M3 ECS Wheel Spacers
4Pc 12mm Wheel Spacers 5x120 fit BMW 318i 320i 325i 330d 335i M3 E34
ECS News - BMW E46 M3 ECS Wheel Spacers
[E46] - Bimecc 15mm spacers (unused) SOLD | The M3cutters