I have my friends bass I am trying to fix up for him. I tweaked the neck and it looks like it should be good right about now. But the action is still wicked high. And the action on the bridge was set pretty low. Should I be looking to put some sort of shim in the neck joint? Or should I try and make the neck more straight? It is Warwick and it has the nut height option. But I don't think this is the problem because it does not look like I can set it any lower. ADVICE PLEASE!!