Thanks, yes that was the centre I was thinking of. Oh, it seemed so central.
I went to Bang Sue 3 times and must have taken a wrong direction from the subway (even though I followed the clearly signposted signs to the vaccination centre).
The first time, we mistakenly went right instead of left outside the building and walked right round to the back entrance and through the building. Second time was taxi from home (Phrom Phong) which took an hour and third time was via the subway but both MRT times involved crossing the carriageway (I can't imagine getting from the subway direct to the building unless they have now made a direct underground connection).
It looks as though my next trip will have to be to Bang Sue again.
Oh, how I miss the MBK facility. The only problem with that was (and has been for 20+ years, finding my way out of MBK)
Thanks again for your reply.