2020 update : JC Verdier La Platine

@ ledoux1238 , for me, the SOTA motor system with the 3-phase motor and controller, is already a good option on its own! Even if the Roadrunner could work with the La Platine, I would certainly try the system with and without the servo! Who knows which would sounds better to my ears. 

$400 seems a good price for the granite plinth! I am still thinking whether I should get a La Platine size plinth or a bigger one modelled after the Basis Transcendence.

About the hole on the plinth for the main bearing, if you have set up the La Platine from scratch, you probably have noticed the hole is a lot bigger than the bearing housing! Being a bit OCD, I tried to center the bearing housing in the hole by wrapping tapes around the bearing housing until it fits tightly in the hole! Then I found out the screw from the bottom could not lineup with the bearing housing, because the screw hole on the bottom steel plate just wasn’t centered with the bearing hole on the plinth! 

I have always wondered whether the big bearing hole is a design feature so the bearing housing has minimal contact with the plinth, so as to minimize (?) vibration transfer from the plinth to the bearing! However, I think it is more likely just a necessity for the lack of precision drilling of the screw hole on the steel plate! For the granite plinth, I am thinking of just using a big washer, or a heavy nut like those used under tonearm mounts, in place of the steel plate to tie down the bearing. So, the size of the bearing hole on the plinth is probably not that important! 

@ledoux1238 thankyou very much!

@thekong 

Thank you for all your input. I did set up the Platine myself. However, I do not recall installing the main bearing housing at all. It was twenty years ago and that part of the plinth is a blur to me. I need to take it apart. But from your description, there would be some play. If I move forward with the granite plinth, I would send the locking rod for the arm-pod as well as the bearing housing to China and have them make sure those parts fit their respective positions. 
I took a closer look at the Transcendence table. If it was to serve as a reference, a larger plinth would allow space for a motor pod. I would still use the existing arm pod design and its relative position to the spindle. And still prefer a two arm configuration. And the four isolation footers would require some serious thought. 

The Jasmine motor I am using now is a three phase AC type. Strangely I am not missing much compared to the existing motor, given it’s relatively inexpensive. 

@ledoux1238  , I would recommend against sending the bearing housing to the factory! If it went missing in the mail, you have a big problem, especially when the new Verdier factory has not resume production after all this time. 

When you dismantle the TT, you will find the bearing housing is nothing special, the part that goes into the plinth is just a cylinder, so you just need to measure the diameter of the cylinder and let the factory know how big a hole they need to drill. 

The tie rods for the arm towers are also nothing special, just a long M10 (or M12, I can’t remember exactly) bolt, you can measure it. You just need to let the factory know to use the correct thread insert! 

About isolation feet, if you need the feet to be easily adjustable for levelling, you have very limited choices! I have looked at many audiophile footers and nearly all of them are nearly impossible to adjust levelling once you put it under a heavy TT. You have to find a way to lift the TT slightly, adjust the footer, and lower the TT back down, very troublesome for precise levelling! 

I am going to get the footers used under this TT :

https://www.woodsongaudio.com/plinths/garrard-301-single-arm-classic

The footer has holes on the side, so you can insert a metal rod to turn it relatively easily. The brand of the footer is Track Audio

Is this the Jasmine motor you are using? It is a DC motor instead of 3-phase AC motor like the SOTA ! 

http://www.jasmine-audio.com/cjxl/index_6.aspx?itemid=181

In a Past Life as a ID TT Owner, I had a 9 Stone in weight Granite Plinth.

Granite of a substantial weight not necessarily at 9 Stone is a 'young man's sport', managing it as a material, requires quite careful considerations.

Today I still use Granite in Sub Plinth Designs as a Tier in a assembly of materials, but this is static in the selected position and is not intended to be worked with. The design that is in use for my Power Amp's has a Granite piece in use that weighs approx' 56 Stone. 

For the TT, when tinkering with adjustable feet, the devices shown in the Link will do a good job of taking weight and making the working with the Footers more simplified. The method extends favourably to all TT's with feet that are adjustable.

For the actual Footer used, the Audio Technica AT 616 might prove to be ideal.

https://www.amazon.co.uk/Mounting-Cushion-Lifters-Pneumatic-Installation/dp/B0DRNP2MG4?ref=pd_sl_95bd26f8710d400cad219f96d9d90a6e_e&hvcampaign=116739&hvadtype=1&hvdev=desktop&appid=1014&l=1&tag=uktextadsdes-21

In the world of TT's Supporting Structures such as a Plinth/ Plinth Chassis, changes have occurred in how a TT is designed. Designs are now in place that are no longer recognising Mass only as being of value. Especially when a Mass Material is with very poor intrinsic properties relating to a Damping Factor and Dissipation.