Snowman,

This will give you a bit extra to play around with.
http://cgi.ebay.com/ebaymotors/304-Stain...sQ5fAccessories
Some T4 flanges to choose from.
http://cgi.ebay.com/ebaymotors/T4-Large-...=item20b8e64156

http://cgi.ebay.com/ebaymotors/T4-Divide...=item588e5fd7e3

Yeh,
I would not get an on center turbine housing, they are not as efficient as the standard type turbine housing.

60 MM would be the absolute biggest compressor wheel, for you to run on your stock engine, anything bigger would not work efficiently.

MBHD

12 port SDS EFI