[Jac Mac]

As a rule stainless bolts in heli coils tend to bind, I would also check that you are using the correct bolt thread match eg 5/16" UNC / NC in this case.

Running a tap thru a Heli coil is a recipe for disaster, if you are using the correct bolt thread you shouldnt need to do this if the HC was correctly installed.

To remove the Heli Coil from this 'Blind' hole location you have to grab & bend the top coil out into the hole and then wind it back out with a pair of needle tip pliers. '''IF''' the hole is not blind & the insertion tang is still present then you may be able to remove it out the bottom with the correct installation tool.

Bear in mind that a special tap for each size of Heli Coil is required, not just any old tap.

Jac Mac