Thanks, nicely concise pointer…!
Many more extra characters are then necessary tho (30 per heading, 500 items = 15000), and only 32000 characters per post possible on that forum. Plus 9 for each link, which I haven’t even started on yet (I was dreaming of 2000 
). Simple #-headings’dve been better for that… 
I’ve asked my forum-admins if they could increase the max post length to 150000…. Any further suggestions/ideas on that? Have to rethink the whole linking-dream otherwise, I spose.
(I’m already deleting all thread titles & my tag out of link-URLs to save character-space.)
Reading around I found this interesting extra by @RobMeade: You can also use empty heading tags (but leaves extra “space”).
(For dummies like me: 
My missing term was ‘anchor’… 
‘ids’ = IDs, had to look up 
griefing here. (here: = abuse of styling))