Your collective wisdom was, in fact, wise. I stand better informed and somewhat chastened
The luthier listened to me politely and then said that he wouldn't dream of drilling the holes necessary for a tailpiece that I described in such a beautiful instrument. If the main goal is to gain access to the much larger selection of long scale strings, he said that he has been using them on short and medium scale basses for decades without a problem, especially with larger diameter tuning pegs like the Guild has. He showed me how he squashes the end to be cut before crimping and that was that.
If I am adamant about wanting to use long scale strings, he said he could fabricate a sort of harp style tailpiece out of brass, like Nuuska suggested and like you often see on archtop guitars, that fastens on the butt of the guitar only with the strap button and then right angles over the body without touching it. If desired that could have a wooden decorative piece over it, like you see on Eastman or Peerless jazz guitar tailpieces. Mucho dinero so must be left for another day, if ever at all.
He is going to fabricate and install bridge saddles and a thumbrest out the piece of katalox that I supplied. The thumbrest will have a small piece of thin clear plastic sheet protruding from under it to prevent my thumbnail from gouging the finish when my thumb is on the rest.
He quickly checked the frets and pronounced that a full dressing appeared not to be necessary but will check that again when he lowers the action and installs the new strings (D'Addario EXL 170).
I don't know what you're accustomed to paying for luthier services where you live but Rufus charges $80CAD per hour plus parts plus sales taxes.
Thanks for all the input, suggestions and advice; very much appreciated.