Okay guys, as update and to help any others looking to change suspension now or in near future. My LR is a simple ex-military D90 with Exmoor canvas top and full external safety devices cage. No additional weight, winches etc., and is used purely for leisure...primarily on road with only light off road fun. So, with all your great advice above + some masses of additional online review/recommendations reading this is what I ordered last night.
Fourways:
Std Springs F&R
TerraFirma Dampers Light/Mid-weight Dampers
Gwyn Lewis:
Std Height HD Front Turrets Inc Re-locator, GL1056
Defender Drop Arm Conversion Kit & Track Rod Bar, HD Steel
Four Galvanised Spring Seats NRC9700-4
Heavy Duty Front Turret Securing Rings, GL1053
Flat Pressed Rear Spring Retainers, GL1068
Challenge Front Spring Retainers, Hook Type
My thoughts are that the above set up will give a hard wearing, positively compliant drive for my needs. Only thing left is to choose the steering damper...I become totally confused with whizzy head last night c/o the sheer number of options. Need to order this tonight together with new nut/bolt install kits. I'll post pics in the Defender 'what have you done to yours...' thread and give some post install feedback for all
ps off to Kophill on the 21st to meet with a fellow selling his very smart all leather RX8 seats