Do diffrent heads require diffrent length pushrods?

[Ieatcamaros]

Here is a link from Holley's site that tells you how to verify valve train geometry. It is a pdf.

Here is one from comp cams website.

Here is the adjustable pushrod you need. Well, I see the link didn't do exactly right. It is the shortest one 6.125 - 7.500 range.

This should point you in the right direction. If in doubt, ask.