Just removed the head from my pinto to do the head gasket but I noticed the aux pulley feels like there is a lot of "slack" or play before turning the aux shaft is this normal?

Do you mean bearing slack or gear lash?
Check the bolt is tight
Check you have woodruf key
Usualy the pully to the shaft is rigid, should not be any play in the drive to the distributor either

It feels like there is slack when I turn the pulley as if its not engaging for a 1/4 turn