It will also depend on the size of the base circle of your cam. If you go with a package kit then 7.400 will be fine. If you go with a custom ground cam, chances are it will change. Mine for example are 7.100,big difference.
I have a set of unused 7.400's if you need them,p.m. me. Ether way, it is still best to use a pushrod checker. No 2 engines are the same and you can get better geometry even with a package by simply checking, which = more reliability and power.