Alfred,
Given how long it took me to learn how to succeed in this process, I'm trying to make it really simple for other beginners to find a suitable map. So even though the Thread Finder info might lag slightly behind the corresponding info in other pages, given that time is not usually the most critical issue for beginners (simplicity is), I think I'll stick with my method of just going to the Thread Finder to locate a 'green' map with meta data.
At biggerdave's suggestion, I'll shortly be PM'ing you a draft of my procedure, for checking. I'd welcome any constructive feedback you can offer, before revising (if necessary) and publishing here.
Regards,
Daniel