Repairs Stuck Tranny pulley bolt

The 7/8 bolt that is on the large tranny pulley at the rear of the mower appears to be stuck or is it a cross threaded bolt? I'm soaking it in PB right now but anyone have any tricks on breaking this loose (getting more leverage) given a socket doesn't have clearance due to that frame cross member. At this point the pulley is starting to deform where the screwdriver blade is holding in place.



2007 Troy built pony 13an77tg766