[ghmerrill]

Thanks.  I've been using PDFelement for some years.  It appears to support editing bookmarks.  That would seem to be the most straightforward approach.

I originally mis-read your "frankenbaend.de" address as "frankenabend". Apparently along the lines of "frankentuba", my brain morphed it into "Frankenstein evening".   It seemed like an interesting concept, but then I noticed the error.  That "ae" combination can be dangerous for an English-speaking reader.