The semi-solid BluesBirds had been around since 1967, and this page (with description on page 7) introduces a new completely solid version too. As it happens this is the last catalogue appearance of the semi-solid BluesBird - the equivalent page of the 1971 Guild catalogue only lists the solid body versions.
From 1970 the BluesBirds guitar had the neck-body join at the 18th fret, as shown here. Compare this to the image in the 1970 Guild catalogue, where the older style join at the 16th fret is still in evidence.
The pickups for the JS basses are described as 'Guild anti-hum' and indeed Guild had recently changed to these pickups, however those shown in the illustration are the older style hagstrom bisonic humbuckers. The picture was updated in the next year - see the equivalent page in the 1971 Guild catalogue
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