If you shave the stock head .040 you will certainly increase compression. The head will usually need to be rechambered to maintain adequate squish clearance. With an interchangeable dome head, the chamber design can be machined in many different configurations. There is only so much you can do with a stock head. Some aftermarket heads don't cool any better than stock....some do.

 

With -.030 taking off you'll be fine to run pump gas and that will raise compression about 25-35 psi which will depend on the porting that's done and how high they raise the exhuast timing which lowers compression.