The thing that sets Squier 51s apart from most of the other models we play...............
Is that the hard shell finish acts as an exoskeleton and reinforces a very soft and punky "basswood" body. These range from moderately OK to incredibly soft and crumbly material. We're had guys on the Squier 51 Board who have ACTUALLY broken their bodies in half or more, just doing basic routing on them.
Normally I encourage guys to clean out all the crud in the neck pocket, down to solid wood but there IS sometimes no solid wood. Ream out the holes, Like Ricky D says, and smooth the paint in the pocket, clean the underside of the heel and reset the neck as laid out in Carzee's famous thread. But ignore Ricky's comment about Roycaster being right. Roycaster is wrong, most of the time, what he says above. :^) There's room for improvement on most bolt neck guitars, other than switching pickups and I've seen so much of it to say no.