I can't tell you what's best, but I can tell you what I ended up doing after reading that thread and some of the caveats about using too much lining. When I upgraded to a Basslite, I decided to line the top and the three sides below the amp cutout, leaving the bottom and the upper half of the sides and back unlined. I'm very happy with the results - so happy that I've never actually experimented to see if it could be made better with less or more lining.
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Copied your setup but used foam mattress topper. Read a thread here and a commercial user recommended it. Also implied they have done testing against acoustic foam. They still recommended the mattress topper.
Will see what it sounds like when my bass gets back from the shop. I left the driver stock for now because I don't have the cash to upgrade at the moment. I have a feeling that with the foam in place it will more than serve my purpose.
There are also lotsa Rumblers there.
I didn't even know my 2015 200cV3 had a fan 'til read about them in Rumble Club.