water pump pulleys?

[greyrabbit]

So I'm putting my engine back together and I'm about to put the v-belt pulley back on the new water pump and drat...the new pump has a different pulley hub than the old one.  I'd rather not take everything apart and get another pump, can I simply get the right style v-belt pulley or will it not line up.

Any help appreciated.

[burn_your_money]

I know mk1s are either 30mm or 40mm hubs. I did swap a 40 to 30 once and I had to use washers behind the pulley to align it properly. It's still not 100% perfect but it works just fine (so far)