Yesterday I created a thread asking whether lowering the tuning of a song to suit my vocal range would work, everyone said yes except that Kamelot would require some experimentation.

Today I found a backing track of Run to the Hills by Iron Maiden in drop c tuning, I attempted to sing along with it. The problem was, it was still too high, in the chorus I was still going into head voice while it is meant to be sung in chest voice.

It seems that if I were to lower the tuning to the point that I could sing in chest voice the whole time, the guitar tuning would be in drop g, which I would need a seven string for and I don't know how that would work with iron maiden and other power metal songs.

The highest note I can hit in chest voice is d#4 while the chorus for Run to the Hills goes up to c5 and d5.

How low would I have to lower the tuning or the key to be able to sing that in chest voice.