I happened upon a set of instruments the other day off a '88 100RS, very very tidy with only 27000 K's on them. These are the later model clocks with the gortex and 9 screws.
I thought I would try them on my '85.
On fitting them I find that although the connector block is electronically the same, the shape of the connector pins are different, the earlier clocks have a almost square pin whereas the later ones have round pins, and putting the earlier square pin connector block onto the later round pin speedo, everything works, but the connector block loosens up and looses contact.
I found that by putting a small block of high density foam under the connector cover provides a constant pressure on the connector and things stay working, proof of course will be whether it remains so in use.
So far I have seen 3 different sets of instruments, all slightly different, the original set that was on my '85, with 7 screws on the back, no gortex, 2 fuel lamps and square pins, a later set that has 9 screws, no gortex, only 1 fuel lamp, the abs lamp ( which actually works as the 2nd fuel lamp if fitted to an early bike) and now this newer set with different shaped pins.

A pointless thread I know, but the more I play with these K bikes the more intrigued I become with them.

I have two (your type 1 and 3). I have used both, but now notice that I can't use the original any more as the connectors don't make proper contact. Bummer. I would like to use the original icw mileage etc, but will need to do something. Buying another speedo is out of the question as they are becoming increasingly expensive. Guess I'll need to post a 'want-it' somewhere.

The Haynes ( and geuine) manuals make me laugh, to remove instruments, firstly remove fairing< I can have a set of instruments off in less than 2 minutes, using just a 5mm allen key and either a 3mm allen key or stubby phillips screwdriver, depending on year of the bike.
moral: if you park your K bike near me, don't take your eyes off it for any more than a minute. (lol)

Not sure [ memory fade ] , but isn't the loom/s to the instruments a sub loom that plugs in?

I must have nearly one of each instrument now from 84 - 93 - I didn't realise there were so many small differences [pins, etc.]

No, the loom that plugs into the instruments is part of the main loom itself, not a sub loom.

Robin, no worries parking close to you! But I agree, just need small hands (which don't come with this 6'5" frame).
I thought about fitting the 'newer style' connectors to the old loom, but braking up the old one I have a bit of an issue with. I like to keep things original (probably an age thing!).