On ya Hubz!There is a design problem money won't fix.
Long rod thru engine:
1. Punch a hole in the mainshaft so you can get a rod down to the back of the pressure plate.
2. Have a pressure plate made or find the same maker's pressure plate that uses a liquid lever. Maybe it will bolt up?
3. If you punched the freeze plug out of the mainshaft, that was part of the oil pressure stopper so the freewheelers on the shaft are lubed. Maybe you'll get away with the rod being there or seal that end up with a machined housing of $ome $ort?
4. Machine and weld a slave cylinder to the outer chain cover. You may have to remove the chain cover, copy the bolt pattern and then bolt on the slave cylinder for the rod needs to be pushed.
5. Run a hose up to the new liquid lever off some bike?
Rod on the pressure plate side:
A. Say the chain side or going thru the mainshaft that way is a PITA. Run the slave cylinder on the clutch cover.
B. Since the pressure plate can be pulled away with an arm coming off the top and out of the clutch housing, you'll need to find a way to design the pressure plate to be pulled instead.
C. Bring lots and lots of $$$$$$$$$$$$$$!!!
You can lube the cable and adapt to the bike like a man, or $quid-ON Some Liquid $etup. Show us pics of the progress!