Guys, thanks for your help so far
I was looking at the cam wheels looking for a stamped mark on them - not realising they were actually triangle shaped holes !
The inlet cam as close to TDC as I think I can get is at this position

At the same crank position the exhaust cam looks like this

So I think one of them is out between one and two teeth !
Looking at the plugs its definetly been running rich so I think the exhaust has been advanced and so has not been scavenging properly
As far as the coolant residue goes I'm still not exactly comfortable with it - it looks as if someone has tipped a small bag of snad in there at some point !
Coolant residue in the bowl

Build up on water pump impellor

Now I can see what the issue is with the cams and have a route to solve it I'm going to wip off the water pump and sort that out then bolt all the covers back on and start doing the clutch etc.
Thanks again for your help guys
Cheers
Andy