Thanks to Dave, Phill and dphphoto for your views.
Oddessey Sales had some used glassless carriers, so I've got a 5x4 set, 35mm and 6x6 mm set on their way. After careful consideration, I also decided to get some anti-newton ring glass, so I'm covered for all eventualities. At least then if I want to print non-standard film formats, I can do so without a problem.
Dave, the Devere does have adjustable masks.
Hopefully, the masks plus an adaptor cable for the stopclock pro will arrive today.
All I need to do now is get some AF (why couldn't De Vere use Metric?
) allen keys so I can dismantle the enlarger before moving it from the garage to the darkroom....