Can't get right after refin

[Couvy]

Hi everyone,

I'm at my wit's end with this bass, thought I'd throw it out there and get some others' advice.

I had this bass refinished a while back, just sent out the body. I detensioned the truss rod while the neck was loose. Once I put the bass back together, though, the action was extremely low up high, extremely high in the middle and lower neck. Obviously, I put some tension on the neck to straighten it out, and I've tried shimming the neck to get the overall angle right. I just can't seem to get this thing to act right. With it shimmed, I'm running into a lot of resistance from the truss (as if it were maxed) before I get it anywhere near where it needs to be. It's a 6 bolt Sterling by Music Man, FYI. Anyhow, I appreciate any insight you all can give.

Thanks!