Hey Wayne, Welcome to the fam bud
Good thing about your woman lovig the truck as much as you do is that she probably won't mind you makin mods to it
In regards to question...
2 - The Cruise Control ECUs on D1s are known for goin haywire, so the relay-clicking sound you're hearing could be a sign of yours going kapoot soon..I dont know for sure though, someone else will come in shortly and correct me
3 - I would stick to the 91 as 98 would be a bit of an overkill for compression.
As for checkin for levels, I usually do it when cold and add/drain accordingly.
In regards to lights on the dash, I wouldn't be TOO worried as Discos are known for having all sorts of Electrical demonds, some serious, some just plain insignificant.
Hope I was of any help to ya bud. Once again welcome to the fam
PS. My girlfriend and I were talking about going to Austrailia for our honeymoon after getting married some time from now.
Maybe we could meet up and go wheelin ( I hope I can rent something nearly as capable as a Landy for my stay )
