Hi John,
Yes I love the Harley and the Morgan, I wouldn't part with either

I must admit I was suprised when New Elms suggested 20 psi, they had fitted the new suspension and then went out on a road test and came back with that as the recommended setting.
I tweeked it back up to 22 psi over the following few weeks and realsied they were right and dropped it back down again.
This is all very different to a motorcycle where its best to stick to the manufactures suggested pressures.
That said, with Avon motorcycle tyres you usually add 5 psi ontop of the OE recommended pressure so maybe nothing changes after all
Best try it and see which you prefer, we are all different as you see so often on here!