Thrust washers completely missing from transfer box differential

I've finally got round to stripping down to rebuild the old transfer box from my Defender TD5. (I swapped it for a 1.2 ratio one that I also rebuilt completely when I changed the gear box) As I started to remove components, I kept finding bits of copper like metal flakes in corners of the housings. I've finally stripped the differential down and found no thrust washers around the planetary gears AT ALL. They've all disintegrated and been gobbled up and chewed by the gears.

Is this a common experience? I've made a preliminary look at the bearing surfaces of the planetary gears and I can't see anything amiss at all. The bearings will all be changed and I've started to check for wear on the obvious items like selector forks etc. All are within factory tolerance. I haven't cleaned the gears perfectly yet, but obviously they'll get a very good inspection.

Any suggestions as to anything else I should watch out for? Did I catch the transfer box just in time before the differential imploded? I don't want to throw money at the gearbox because I'm only rebuilding it for my pleasure and to sell it but I will replace things that need to be replacing. (I'll document everything with photos of the components with measurements of the key parts with micrometer and digital calliper so hopefully a buyer will be able to buy with confidence.)

Unless I am mistaken this happens to these washers over time. I stripped mine down 4 years ago and found the same. Given their absence, check to make sure that the gears haven't caused any significant wear on the inner housing of the diff.
I got myself some new washers and replaced the center cross pins with a single piece forged cross pin whilst I was in there.

its normal just replace them

Thank you. The sun gears and planetary gears seem to be unaffected. The previous LT230 I rebuilt had the spacers intact so I wasn’t sure whether finding them all gone was particularly worrying or fairly normal.