The normal way to be really sure is to use the Dynamic Configurator at Cisco and try to build a router with the bits and bobs you need. If you are missing something, it will bitch and moan.
Really, the VWIC depends on the chassis, and the VWIC2 certainly works on a 3845. Nice big router - only one E1 eh? That's a bit of overkill - why did you want the 3845?
Now this is the Contact Center forum, so I'm wondering if this is a CVP question. Or maybe you are lost. ;-)
Regards,
Geoff