speedo drive question

Hi again all
Can I just check somethings please. My drive was seized solid so I've stripped it, cleaned and grease it. A match stuck in the end will freely spin when I turn the metal flap which I presume locates somewhere in the hub. So far so good BUT
My three questions are:
1) should the circlip keep the drive sealed together? mine will now separate but I appreciate the fork links and a nut will stop this when fitted to the forks - mine didn't before so I am not sure whether this was because it was seized or I have done something wrong.
2) I have small spring sat in a small hole half way down the tube where the speedo drive and cable would push into it. What is this doing and should there be some kind of screw or cap that sits over this?
3) finally how does the speedo cable itself stay in place? does the brass housing remove somehow? I've tried tentatively and it appears fixed / solid on mine. Currently it looks like i''ll just have push it in / pull out option for the inner cable and no way of secure this except for some sticky tape.
sorry to be so needy / thick
Mike

Hi Mike, here's some pics of a speedo drive in situ and a N.O.S drive to perhaps help you out. The black rubber cover at the end of the cable is off a G.P. I hope these help

Thanks Thackers
That is really helpful. They are quite an odd design in my view! It looks like I'm pretty close, mine looks like yours. but I'm going to struggle to find a grub nut to hold the little spring in place. I do like a bodge!
Thanks again
Mike

great pics Thackers, very helpful.
Mickey, not sure about this spring, could it be a coil of metal from the outer cable of the speedo cable ?
on some of the drives they have a threaded brass end, and the bare part of the outer cable threads part way into the brass end.
daz

The spring looks 'proper' / intended original part & is located under the dome on the shaft where the cable slots into (is it called?) the worm! The dome bit with small bolt or similar is most obvious in the last photo. As I say no idea what it could be for but I'll bodge it.
Thanks again all

Mike, I think you might have a drive unit like the one that scooter restorations have in stock, the dome with the nut is a grease point. There's is slightly different to mine as the one I have doesn't have a nut. Above all make sure your cable is the correct size, there are 2  and they don't cross over this will be most important at the speedo. Scooter resto's have both size cables and the speedo drive, you might just save a load of aggro and buy new.
Cables £10 each
Speedo drive £35
@Cam Lam speedo drive £36.70
Rimini
speedo £65.40
drive £54.50
cables £7.30
Or you could try phone Armando's at sheffield

Thanks again for the advice - of course it's a grease nipple I need! That's doable! I did consider getting a new one but with a nipple attached & given it does spin a match, I think with your collective help I've cracked it! Could be famous last words but I am seeing progress, thanks again. Next job is getting the forks built, no doubt a head scratching post will appear soon as my 1st attempt got me no where.