Just acquired a 2009 360/12. It is my 1st Ric.
Going to be cleaning it and putting new strings on.
What is there that I need to know?
Its in good shape but I did notice the bridge is tilted so I will be addressing that.
Any good starting measurements for relief and action?

tilting the bridge serves for intonation if the saddles have reached their limit of travel, tilting or raising the front of the bridge moves the saddles further back away from the treble pickup, allowing for more adjutment, tilting or raising the rear of the bridge moves the saddles closer to the treble pickup for the same reason.

action is a compromise between string gauge, bridge height, fret buzzing if bridge is too low, and tuning issues when fretting. So if you want really low action you will get some fret buzzing unless you are an expert in neck adjustment.

using a digital tuner to tune the strings in their open state does not guarantee that when you play or fret a chord, the strings will be in perfect tune with each other.

I have learned to tune by ear particularly the A and D chords and the heck with these tuners. If it sounds in tune when you are playing an A or D chord, it will probably sound out-of-tune when you strum all the open strings. Again, it is a compromise, there is no perfect anything, you are dealing with a somewhat flexible wood neck, humidity, or lack of humidity, string tension, and a million other factors.

I am not a technician but I have played my 370-12 for 50 years, go figure.

by definition, the 3rd of the chord (f# on a D chord, c# on an A chord, etc.) will sound sharp due to the approach to equal temperament that is the purpose of having twelve progressive frets per octave. So don't try to over-tune the guitar.