RC040 style 5 faces on RC090 barrels? (e36 m3)

[lo e36 m3 ol]

Wheel Info:
-BBS RC040 style 5: 17x7.5 et40, 2 piece split
-BBS RC090 style 5: 17x8 et20, 2 piece split
-this is for fitment on an e36 m3

Would swapping the et40 faces onto the 17x8 barrel make the wheels fit better and closer to oem or would it not really make a difference because of the extra wheel width?

thanks in advance guys :redspot

[e code]

I believe it is the barrels that determine the offset on these. Correct me if I am wrong. A 17x8 et 20 will put the lip of the rim closer to flush with the fender than the 17x7.5 et40 which would sit more sunken in.