@Rick's Fine '52 is correct, of course, stating that the 3-knobs started around mid-'61. I've seen quite a few examples, in person as well as on photos (some very detailed among those). In my experience, you can find both configurations for the second half of the year.
I've yet to see a 1962 stack-knob though, at least a well-documented one. The only one I recall was from a senior contributor on the now deceased Fender Discussion Page who said his was a 1962. Not much evidence or details given, if I remember correctly, so difficult to verify.
The Bass Gallery bass could really do with an in-depth description. Two of the pots are obviously replacements, along with the bridge. You'd have to see the instrument in person in order to tell whether there is any overspray - the vivid Red however is typical for a 1961 Sunburst.