How much glycerin to my standard (7oz?) FW bottle would you recommend?
I have been pretty haphazard with glycerin in concocting homebrew AS. The FW might be a good test bed, try to get the titration dialed in.
I'd start with not much! Also, until you have an idea, decant into something else and try! You can't get it back out ... But once when I did just that, I got another bottle of same aftershave and diluted the tacky bottle for the win!
AA