Bridge alignment, to me, looks ok but I'd be askign what the seller means by 'carefully rebuilt'. It looks a very clean guitar for a '76 model. Have you dated it? You might also ask to see the control cavity and the front pup cavity and cable rout. Plus, if it is a 4001, you must ask to see the truss-rod ends: if there are two (as there should be) and they're bending downwards, the truss-rods are probably buggered.