[Cory]

Using 7075 or 7068 for the sideplates of a drivetrain is a total waste of money and complete overkill in my (not) so humble opinion. Tons of people have made similar designs with plain old 6061 and it works just fine.

It's always better to figure out why a design actually works and the best ways to implement it than to just assume upgrading to a "better" material will make everything work.