Hi Cal -- The Fuji is likely to have an AF focus-confirmation indicator light in the viewfinder, as the Leica S2 does. This should continue to work even with manual focus lenses, as a handy focus aid. The S2 meters fine with the manual-diaphragm setup, hopefully the big Fuji will too.
For some juicy 75mm AL photo samples... 🙂
Go the RFF Gallery... choose Gallery Search on the gallery menubar, choose Advanced Search, look down to the popup menu labeled Select Lens Used, click and hold on it and scroll down to the Pentax 67 section and choose the 75mm f/2.8 AL. You’ll find three pages of photo thumbnails of pics shot with this lens. Oddly, they’re all mine! The first 26 pics, the most recent ones, were made with this lens on the Leica S2.