Can I evenly extrude these faces???

These screen shots should help you understand what I’m trying to do.

select faces then press space type “solidify” and use a negative #

That works great!
Only issue I found that may be a problem in future models is that if the edges are angled differently than say 90 degrees, the result may not be what I want. It also leaves behind the original faces.

@John_Lancaster got a blendfile for your example?

Also can use Zmj100/1dinc’s extrude along path script for this too.