so my rear left brake is really tight, like the brakes not engaged, but its still hard to turn the hub. possible culprits? ill be going home tonight to finish up the radio install and shift alignment.

Could be a lot of things:
stuck cable holding it on
pads stuck in the caliper
pistons stuck in the bores
rubber brake line pinched inside holding pressure on

Check each one out, then we can help with solutions

Could also be incorrect venting clearance.

with both