Dear Chris, IF... (and this is very important)... you keep the 2 big bolts also, to maintain the contact firm, then...
the spike couplers under the 7mm Brass armboard are using the same logic of Orsonic headshells & Midas Touch indermediate headshell weight : They provide a clean (rigid coupling without soft materials that have any compliance) but short path and thus allowing only a fraction of the resonances to pass through the next level.
This is not counting as an isolation (rigid coupling of metals) and it seems that it works for cartridges !!!
Now I'm thinking an alternative : As the 2 bolts are allready provide a path from Brass armboard to Aluminium armpod, you can cover the entire underside surface (except the 2 holes) with a very fine velvet textile (extra thin without compliance) in order to damp the 2 metals that are coming in contact. This is a very different option from just applying the silicone oil to the same surface. You have to choose by trial & error these 3 options unfortunatelly we cannot predict the results. Depending by the mass of the armboard, (and especially the tolerances in execution) the 2 bolts may not be enough for the 3 coupling spikes option and can provide space for ringing or even worst a possible diformation of the Brass platform. I would prefer : ability adjustment only at the bottom spikes, the steel discs about 6cm diameter and replacement of the upper coupling spikes under the Brass armboard by very tiny bearing balls (if you decide to try this option, by this way becomes easier. Although the marking points of the Brass armboard & the Al armpod by the bearing balls is of no concern 'cause they can only form a round scuff, I'm anxious about the proper amount of tightness by the big bolts).
Of course anything soft under the discs makes the whole armpod isolated from the shelf, interrupting the passing of resonances from armpod to the ground and it needs experimental verification also, since it is only depended by the shelf prorerties.