No worries on that score. My bearing is largely unworn and I use it rarely enough to keep in that way. And after tuning up the suspension, I wouldn’t want to have to do it again after putting a record weight or some other doodad on it.TD166 eh? I have some upgrade ideas for you and sometimes, eBay is your friend for parts... Just DON'T use a record weight as the main bearing thrust plate isn't the strongest (I have a well loved/used TD160mk2 here and the well loved bearing was worn out until I added a 1mm ptfe pad which has fixed it, at least for now)
I did replaced the plastic pulley with one of those aluminum jobs, and I use an external power supply (a Music Hall Cruise Control) to allow the use of only the larger pulley (and not the derailleur). I adjusted the bearings in the tone arm, meticulously aligned the cartridge, replaced the rusty springs, and made sure everything else was in a state of good repair.
And I bought a new dust cover, and installed a Q-up.
Oh, and I replaced the bottom cover with one that has leveling feet, and put that on an isolation pad that I didn’t actually need.
Rick “no need for further tweaks” Denney