Jim,
I have never progressed after modifying up, down and sidewards my pen mill it still is an unfinished project with life challenges I am not a believer in sharing some things (others using them) horrendous experiences with trailers etc and try never to borrow anything so I will sit this one out and observe having exhausted the subject many times over the years.
A thought would be find out from the English distributer of the Beall and get a list of successful users ask them to show you examples etc. When I first received mine I was full of the milk of common kindness toward everyone, the first thing I did was photograph in detail all my modifications and send these to the manufacturer who was extremely offhand with me complete disinterest would be my assessment I felt the word precision was a misnomer as well.
Now to all users of Mandrels that terminate on a point contact you will not be surprised with the fact that high on my list of total dislikes was this method is employed in the Beall.
The main drive stem has a whoop in it on the phone to Mr Beall I asked could I buy an upmarket one another weakness IMHO his reply to the effect what do you expect for fourpence crayfish etc etc.
Anyway since I do not have a dog in this fight only feelings based on fact I would be prepared to enumerate a few things using my pics when I can locate the pics.
Already you have your home grown expert Grump who can agree or disagree with my assessment as a previous dissatisfied owner.
I just observed that far from standing back I have a dog in this fight. Do what I can to be helpfull.
Kind regards Peter.