Want to update 20 year old LP12/Grace-what arm?

Just got a used LP12 which is allout of allignment but think works ok electronically.Ectremephon told me to just see if I could do adjustments myself but thinking about turning it into a project.He warned me that a basic "tune up" is a waste of money at aound $200 but thinking maybe the cirkus thing for $400 might be worth it.Thoughts?Also I was thinking of replacinfg the old Grace with a RB300.But I have a freind who will give me his AQ PT6 for almost nada.Oppinions ladies/gentleman?
I just got a used LP12 a couple months ago and I paid a local Linn dealer $50. for a full tuneup. It was more than worth it. Of course I was lucky as there were no major structural or mechanical problems. But Linns are extremely finnicky. They must be set up just right and they must sit on a level platform. Once that is acheived, they sound superb.

As for the Rega RB300, you cannot go wrong. Just take a look at all the high end turntables that use this arm as their stock arm.

If you do decide to do it yourself, here are a few tips (I'm sure there are some that I do not know):

The turntable has a very particular structural design to minimize vibration. Almost anything that affects the structure or its relationship to its surroundings should be closely looked at.

When leveling, first level the platform and then level the turntable on a level platform. The unit was designed to isolate vibration best when it itself is level.

Linn says the unit is best designed to handle vibration coming from normal home furniture, rather than ultra heavy pieces. They recommend that the unit NOT be placed on a ultra heavy base as a heavy base transmits more low frequency vibrations for which the unit is not optimized.

Make sure the internal wiring is resting in a way that it does not impede the suspension.

The Cirkus upgrade is well worth it.

I still recommend you let your Linn dealer do it the first time. Maybe he'll let you watch.
I am using the AQ PT6 on a VPI 19jr and very harry with it. It is a straight-forward arm, no gimicks and faily easy to keep up to shape.
get a safety raiser.
Happy listening
re the grace arm - it was a quality arm at the time and is probably as good today (unless its worn out or damaged). what is improtant is matching the mass of the arm to the compliance of the cartridge, i.e. high compliance cartridge = low mass arm. low compliance cartridge = high mass arm. this will help eliminate subsonic rumble which can screw up the bass. but you knew that.