"...it was the use of Brasso that ruined the Papst Motor. The chap that had my Source before me used to polish the platter, sub-platter, motor pulley and mains plug, and some brasso must have run down the pulley onto the shaft. Now I think it's ok to use it on the main platter then wash it to remove all the Brasso but don't use it on anything else.
I use a foam cleaner on the platter and rinse it off with water and I don't clean the sub-platter and definitely not the motor pulley. "
I would add that if you want to clean any belt residue off the sub platter or pulley, use lighter fluid, and use kitchen roll/ paper towels to collect any excess.
If you do use Brasso, it can be messy, so use an old pillow case and hold the platter inside it, working through the open end. That way you can avoid handling it with your bare hands, and also protect your clothes (and the sofa you're sitting on while you watch telly to relieve the boredom of polishing....)
If using the Brasso liquid, use a cloth to put it on with, and a separate clean soft cotton cloth to polish it off after it has dried. T shirts are good for this. If you use the wadding, like Duraglit, don't be mean with the quantity - use a fresh piece when the old bit gets tired.
Plenty effort at the application stage means less work at the polishing stage. If you don't like the idea of regular polishing, consider a spray lacquer after you've done the polishing. If you feel the need, after a few years you can remove it with some thinners and re-polish. But maybe you like the physicality of the whole process.
You can always stick the platter in the dishwasher, once it's polished. If you use the stuff for making tumblers and glassware sparkle, the platter will stay bright longer. Just make sure it is dried completely.