You're welcome, and wow is that thing in nice shape!
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Leave it alone and enjoy it and wait until something breaks...
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Only problem with that is if a power supply electrolytic cap goes down, it could take the power transformer along with it. Even if it doesn't, they usually make a mess and a very bad smell. Not cool. And if the horizontal output tube grid coupling cap gets leaky, the output tube could draw excessive current which places unobtanium flybacks at risk. The first roundie I ever had (a CTC-9F still owned by another member) ran perfectly on all original parts just like yours does, but upon closer inspection there is usually more going on than meets the eye.
If I moved the horizontal centering over to one side, it was possible to see the edge of the raster. Then it was apparent that the power supply had visible ripple in it, because you could see the 'waves' in the image right at the edge. Then I realized the entire image was slightly undulating, which was enough for me to pull the trigger on the power supply caps. Once replaced, the image stopped doing that and the power supply was much smoother.
The sweep boards sometimes have wax caps still in them, and it's always a good idea to check for out of tolerence resistors there as well. That will ensure the sweep sections don't go down in flames, and probably make vertical and horizontal locking much more stable in the process.
Lastly, the set might LOOK right but taking a few readings may reveal more going on under the hood. I always make it a point to read horizontal output tube cathode current first thing after I power a set up, just to make sure the horizontal is stable and healthy. You're looking to draw less than 200ma whenever possible, sometimes the Sams will give an exact value. You can tweak the horizontal linearity coil to get the lowest reading possible. Also try several different HV rectifier tubes, since they are all different and when gassy won't work as well (or at all). Next check HV regulator performance: install a 1ma current meter in the cathode circuit of the 6BK4, adjust the HV pot for .8ma with the brightness control at minimum. After that, verify HV is stable at whatever Sams calls out (my RCA book says it should be 23.5Kv).
After all that play the thing for several hours, and if the horizontal output cathode current is stable and the flyback is not hot you can safely place the set in the daily watcher lineup. Even if it's cool, I point a fan at it just to make sure. Flybacks are the last thing you want to go bad.
