I run a 110 CSW with auto box, 3.9 pre serp with 10/40 semi synth, it's happy as Larry, and a 4.4 RR 0/40 fully synth, that's as happy as a sand boy! Just go for the best spec that's cheapest.
somewhere hid away, in a place accessible only by a fully trained marmoset monkey, an earth connection will look ok but it will be rusted under the nut and/or strap.
Silkolene PRO R 15w-50 , Silkolene PRO S 10w-50
Motul 300V 15w-50
Mobil1 15w-50
if using for competition or giving it some stick, fully synth Mobil 0w-40, Castrol RS 0w-40, Amsoil 5w-40 or Fuchs Supersyn 5w-40 the new rangerovers use 0/40 or 5/40
Does it have an immobiliser? they can have little PCB's that corrode over and short out over time and disable the ignition. If so, rip out the nasty beast and you'll be up 'n' at em!
That's something we could do if your interested, not too expensively, just done it to one of our own vehicles 89 110 CSW V8, we're near sheffield and have a beaver tail transporter so could collect & drop off if required. I'd recommend a 3.9 pre-serpentine with ZF auto. We'll sort the efi. Both cheap to buy and easy to work with. Drop us a line advice is buck shee ! Ask for Paul (Marsie) 01909 552288