I've done it; used a small axle stand
to prop it up and the hose was held in place by a spring clip and so I got that off. Then I put it back down without the hose on... and a pint or two of water appeared on the floor!
Anyway, given that I'm at least 7 miles from the nearest professional repair shop, I'd guess that I'm saving myself at least ~£60 (North Oxfordshire prices) ?
I'll have a look at the pressure switch when I put the new hose on!
B