With the frustrations of the mechanical clutch mechanism and my flailing about not knowing what to do or expect, the obvious answer was to get the books out.
To add a bellcrank and lever was a non-starter - there just wasn't the space or suitable place to mount a bellcrank, and even if there was, additional mechanism would clog up the area I'd earmarked for the heater matrix and associated pipework - Miss X would not be happy with its exclusion. So, hydraulics it is (there's one more option if this fails - cable, but that involves even more complication).
My reading tells me that an ideal pedal ratio is somewhere between 5:1 and 7:1. Right out of the gate I'm missing the mark with a 4.35:1 ratio and because I'm using a proprietary vintage pedal box casting which fixes the critical dimensions, I'm stuck with it. I can expect to exert more effort on the pedal, but given that modern systems are so light, maybe that's not going to be too much trouble.
Crunching the numbers came up with a couple of options of which the second happily coincides with the Landrover Series 2 setup. The slave rod will travel only 22mm of its potential 30mm (73% of the pedal travel) but my observations (always risky) appear to indicate that that will release the plate sufficiently and provide for just enough free play. The bonus is that despite the pedal requiring more force, in return I get 136% effort from the slave cylinder. I've ordered a master and slave cylinder at 3/4" and 7/8" respectively. What can possibly go wrong?
The refurbished Morris 6 clutch plate complete with its new Ford centre splines arrived during the week. Assembling that and the pressure plate to the flywheel made no difference to the distance the bearing face contracted into the mechanism - I was hoping that it might not go so far, thus reducing the travel of the release bearing needed to disengage the drive.
After rebuilding the Crossley's Stromberg, we finally had a satisfactory result. It didn't look as though it was going to work, but adjustment to the needle which controls the flow of fuel from the float chamber to the choke encouraged it to come to life.
A warning to Crossley owners: never leave the rocker cover off when running the engine; this puddle was well on the way to becoming a slick before we noticed.
There's one final irritation to deal with - the fuel supply. Naturally, a car of this age is more than likely to have an Autovac system, and these can operate very successfully for decades without a problem. This one has what I think is an air leak in its top chamber and will have to come off for examination and renewal of the main gaskets. I'm hoping that the vacuum valve is seating properly and not causing trouble as that's a real fiddle to get at and involves dismantling the factory set parts. Otherwise, the car's running very sweetly; the compressions are all even and it starts on the button.
And as the sun set, it was time to get back to the books.