Will Mesa still install.....

[Juggernaut]

an EQ in an Non-EQ loaded Mark III?

I know they used to, but wondering if they are still doing this or not.....

 

[Restless Rocks]

That would depend on if there are any remaining MkIII/EQ faceplates left. Give them a call to find out.

 

[CoG]

Not worth the money dude, just get an eq pedal or buy a different III with an eq.