Bonneville Valve Clearances

I am planning the 12k service on my Bonnie EFI and wondered if anyone had any tips on the valve checking and adjustment part of the service.
From what I have seen it is a reasonably labour intensive strip down to get to the valves.
Not knowing what size shims you need until you can measure the gaps, are service kits available ?
I don't really fancy leaving the bike stripped down while I order parts and wait for them delivering.
I am sure there will be a few on the forum who have done their own valves, so any info would be greatly appreciated.

 

I'm pretty certain they are 25mm dia.

 

Cheers Pieman,
I was getting a bit concerned that nobody else on the forum had ever adjusted their valves.
I am an apprentice trained toolmaker so micrometers and feeler gauges are like second nature to me but thanks for the tips.
I always like to prepare myself as thoroughly as possible so I have watched YouTube clips and read up on the job, but there is always something that you can learn from someone who has actually done it.
I have resolved myself to the fact that if any of the valves do require adjustment after taking the measurements then I will have to order the correct sizes and await postage. Swapping the shims about to bring all valves into tolerance sounds like the most economical way at £6ish a shim.
It might be that none of them require adjusting.
Is there any risk of the cam gears springing apart when removing the camshaft ?
I see that a stepped dowel is required to hold them in situ!
Lot of bits to come off to get to the bloody things.

 

Cheers biglad, yes I've seen that video and it is very good.
Surprised Delboy hasnt done one yet.
Very interesting post from H.O. though, I reckon if the valves have been set correctly from new and you have changed and used good quality oil at correct service intervals they might not need adjusting. Wishful thinking, but I will check them at 12K for peace of mind.