[Humble]

I just did the '86 944 aluminum trailing arm swap on my bug, and the difference is more than 22mm. it's more like 74mm. i'm not sure if even c2's would work with this setup under a ghia, either way it would be very close. the rear hub face on my beetle is 1-2" from the outer edge of the fender as you look at it from behind.

also i'm not sure what the back spacing is on c2's but if it's more than 6" it'll be a tight fit.