Cheers Graham.
I'm thinking of just doing the head gasket as engine has been rebuilt 18,000 miles ago, I have checked the heights and all looks ok according the series 2 handbook.
Then incremental torquing upto 40 lbs (10,20,30,40) following the torquing pattern as per handbook. Then get run it up get it hot, cool down re torquing, then 100 miles and do again. (Dam fussy these AC's)
I am going to Hylomar blue as handbook suggest using Hermatite on gasket.
Have flushed a little muck in water jacket and run around inside it with hoover (old Dyson with a very narrow adapted tube) to clear it right out. Not much in there at all, mainly at the rear 2 cylinders, guess that's down to lack of water flow that far back. Will possibly investigate drilling and tapping block at rear end and run a water pipe to it to aid flow later in year if gasket works out ok.
Now to get a can of high temp paint for head, and clean up inlet manifolds for when carbs come back.
Cheers Gary