I have them fitted to my swb 2.2d
As for engaging them for lubricating the axle components I don't bother getting out and engaging them I simply engage four wheel drive and off I go
50 years old or more makes no difference to brake downs,it depends on all sorts of unexpected problems
Series land rovers have traveled the world for many years
No one needs a Lame cruiser to overland
I find with old land rovers to get any speed out of them you have to drive them like you stole it
Many be you need to change the diff's for Range Rover diff's,that what l did to my 2.25 diesel