Ritchiepok:
First, what size of screw did you find that fits those 2 holes on the platter? I took my platter to a hardware store once but did not find any available screws that fit.
If you tried to lift the platter with inserted screws and the base came up with it, it likely means that there is corrosion in the copper center hole that made it stick to the spindle. See if some WD-40 around the spindle can loosen it. On the RX-5000, there is nothing holding the platter to the base other than gravity. I had similar problem with my other DDX-1000. For years the platter refuses to be separated from the base until I gave it a bit brute force after other owners told me that the platter separated easily on their units.
On the other hand, there is nothing to lubricate in the bearing. It is a sealed unit and I do not recommend you open it up. You should try to get the platter loose however just so that the weight is more manageable if you need to relocate it.
Lastly, remember to connect a ground wire to the bottom of the base before you set up the rest. It will prevent static charge being transferred to the phono stage.
