Thanks very much for that clear explanation. I can't wait to get hold of a set.
In my observation the front suspension on the Morgan does effect the comfort of the ride, as you pointed out, with that kick in the back. The harshness of the rear suspension is felt more in the seat of the pants and in the noise of the sudden jolt as the rear wheels hit the bump or pot hole.
I am planing on eventually fitting 195/65 R15 tyres which have 10 mm higher side walls and then get the rear springs sorted. I need a set of 4 leaf springs that will give me the ride hight of the 5 leaf springs less 10 mm to maintain the ride hight I need with the higher profile tyres. I know I can adjust it with a spacer but I would hope to avoid that if possible.