Sounds proofing for the SVX?

[irox]

I've always thought, once I get all the other things sorted out (especially things that make noise like wheel bearings), it'd like to improve the sound proofing of my SVX(s).

Recently I saw a sound proofing article (about a VW) on hackaday.com which got me thinking about it again:
https://imgur.com/a/yC3Qz9X#mMr7HxL

Has anybody improved their SVX's sound proofing (which was already better-than-average-for-the)? If so, I would like to hear about what you did and how well it worked.

Cheers,
Ian.