Yep, neck plate date is definitely '71, and from the natural patina of the finish I don't doubt it's a '71. The Clapton story is certainly wrong based on dates, unless he bought a couple more. Removing the neck does not hurt the guitar at all. It *has* to be done to adjust the truss rod. Necks are commonly removed to verify dates on vintage pieces where there are neck stamps. Verification on one like this is threefold plus - neck plate (which is easily switched - I have a "reverse plate switch" problem , a '62 Jazz bass with a '68 plate!), neck stamp, pot dates, and wiring, finish inside cavities and neck pocket, pickups, solder joints, and any pencil marks. This guitar should not have solder joints touched unless there are failed pots, pickup or jack. I suggest not doing much in the way of polishing (just clean it). It'd likely be a nice player, but the other option is selling it. A '71 like this with the case in that condition (once the year is verified), even with minor corrosion, may fetch a premium over Vintage Price Guide high "book" price. And that's not an insignificant amount!