2004 grand caravan

hey, i’ve got a 2004 grand caravan with rear disc brakes.
i cannot get the the discs off to replace them. they are loose (after some gentle persuasion) but they will not come all the way off.
do you think it can be a parking brake issue?
also, the caliper bolts on the driver side seem to be different than the passenger side. the passenger side bolts came out easy using a 7MM hex.
but we couldn’t even get the 7MM in the drivers side bolts.

thanks, any suggestions would be appreciated.