In regard to the heads, there is an excellent writeup on the gains for porting and back-cuts on the valves.

http://www.moparmusclemagazine.com/techarticles/5115_cylinder_heads/

This article tells you all you need to know about the steel heads. You can compare these numbers against the published numbers for the Eddy and Indys.

If I remember correctly, the back-cuts on the valves will give you more gains than the Mopar porting templates. I did both on mine and I don't think my engine shop charged me more than a couple-hundred for the extra work.