The 266 was a pretty good machine in stock form, so not sure if the clock would "need" upgrading, since the importance of the latter was quite well understood by this time. have a look at the line output stage to see if a careful recap could warm the tone up a little?
The CSA14 pots look like Alps Black Beauties, which were well thought of weren't they - supposedly better than the standard "blue" version?
SL10 re-do? YES PLEASE!!!!!!
Tear down these walls; Cut the ties that held me
Crying out at the top of my voice; Tell me now if you can hear me