Very many thanks to you all for your posts.
I am tempted to follow Purple_Martin's idea:
On the other hand, because there is a fair amount of VBScript behind the form, it might be neater to read up on the great tutorial provided by j_anstice. Yes, it does seem to cover just what I was looking for. As oilman suggests, a couple divs and floating the relative should do the trick!
At least with the link I have something to go on now, and if it becomes a problem, I'll follow Purple_Martin's idea.
Many thanks again - I'm grateful!