Parenthesis instead of brackets

[Mel Melcer]

Hi, I'm new to Karabiner and need only some basic modifications to the number pad I use to enter formulas into excel. I want to chance the F14 and 15 keys to give me parentheses( ), but the only quick option is brackets [ ], which doesn't work for me. 

Could anyone suggest how to get the parentheses?

Thank you!

Mel