Pulleys!! - They can be a real pain in the neck. Chevy used a gaggle of different ones and you're correct in thinking there are some that will not line up with others..

These guys really know their stuff and they are reasonably prices. Check out their web site and if in doubt, call them and tell them exactly what you're doing and they will be able to fill you in with pulleys that work and line up exactly. They have a pretty wide range of products from real reasonable to real expensive so I'm sure they can help.

www.cfrperformance.com go about half way down the page and click on the Chevy crankshaft pulley..

Here's a link to a pdf of their catalog as well.

https://www.cfrperformance.com/v/CFRCatalog2009.pdf

Good Luck,
Glenn