Turntable placement help

Well the floor is hard to beat. My Basis 2005 was on MDF on the floor for years. Here is what it takes to improve on the floor- https://www.theanalogdept.com/c_miller.htm
That's roughly 500 lbs of granite, concrete, and sand. On the bright side, under $100 in materials (if you skip the granite).

I would avoid putting the turntable on the low slung piece of furniture. From the point of view of the turntable that thing is nothing more than a great big vibration antenna. Every sound and movement on or around gets amplified by its five feet of length and while you probably can't feel it you most certainly will hear it. Right now you are used to the way it sounds on the floor. You're assuming it will sound about the same on the shelf. Put to the test, it will fail. You'll need ten times the mass trying to get it to sound as good as it does now on the floor.

If you just want to raise it up to a more convenient height a cinder block or two will come in real cheap and handy. Drape some nice fabric over it, wrap some more nice fabric around your MDF, put the turntable on top, boom you got a pretty darn good turntable rack for next to nothing.

If you have carpet, some marbles, cones, anything hard and small will go under the cinder block and help stabilize it from rocking.

Yeah it’s hollow but I wondered about those AC pads and a bamboo butcher block between the turntable and shelf.

anither thought is to move the tt 6 feet to the right and put on something. My records are right there so that would be nice. I’m guessing my phono preamp would need to move with it and then I’d have to find some 2-3 meter interconnects to string it all together.

I would avoid that if at all possible. The two things that have the greatest impact on sound are the rack/shelf and the interconnect. Anything more than 1m and your interconnect cost shoots way up while at the same time there are a lot fewer to choose from. Especially used, where the deals are. 

Your table being the level its at is kind of light and will greatly benefit from a solid stable and most of all heavy base of support. The standard of DIY cheap construction for many years is the tried and true sand box. Some guys use a lot, and the more massive the better it works, but you can get a lot from as little as 1" deep. The sand box goes between the rack/furniture and butcher block or whatever you want to set the table on. This does not btw have to be one big shelf. It could also be four smaller pieces say 4" square or round. These kinds of things are very cheap and easy to make and if you experiment a little will be surprised how easy it is to hear the difference and come up with one that works best in your situation.

This is not like most guys seem to think a matter of doing the same thing someone else did. I've done a ton of this stuff and learned some really useful principles but the main thing I've learned is you never know for sure you just have to try and see.

Instead of a sand box you might for example make some sand pads. Anything from larg jar lids to 1" section of 3" dia ABS filled with sand. (Always mix sand with a little oil, or it scatters all over the place.) Then if you also cut a piece of MDF the right size to fit you have what looks like a little round puck filled with sand, highly inert, and you can tune it to your situation easily by adjusting the top material and thickness. In very little time you have turned a problem into a full-on vibration lab learning experience.