Hey UG! I recently purchased a Peavey Mace VT 212 combo for a steal. It is very clean(no dust whatsoever) which is insane as this thing dates back about 30 years. It sounds great but I know it needs a total tuneup. I'm a noob to tubes so would like to know what else to replace besides electrolytic filter caps, tubes, and speakers(it still has the stock emeinences with HUGE square magnets). I am also having trouble finding info on what speakers to drop in it. I can't break the bank but I do want speakers that can handle 160 tube watts, even if I never get it that loud(scared?...maybe). Anyways, I really hope to get some good info on this monster.
No reason to replace the speakers, really. Obviously if they're not working you'll need to, but in general they don't need to be replaced at regular intervals like tubes or filter caps. Even the filter caps are probably all right but you might as well replace them if it's going to be your main amp.

Nothing else should need to be replaced if the amp works fine. Pots if they're scratchy, check resistors for heat damage, but if the amp hasn't seen much use you could probably play it for a few years before it even needed tubes. Depends on how cautious you want to be. I'd get a spare set of tubes, you'll need them anyway, and see if the stock ones are good. Filter caps are optional, probably good for a while but replacing them won't hurt anything. Speakers and everything else are optional, no need to replace any of that until it goes bad.
I have purchased several vintage amplifiers over the years. In the US I have had good and bad luck getting speakers re-coned when they need it. Just another option to consider, but the downtime can also be quite long (many weeks sometimes). But it is about the only way to get the "original" sound back.