So.... plugs all look good, nice light biscuit colour, 25 thou gap, Oil changed in dashpots to 20-50, points gap re-set to 15 thou. Compressions checked all 160-169 psi hot.
Took it for a run and all was ok... for a short while...then when under load it hesitates when the throttle is slowly pushed down, maybe not a full misfire? What about a weak mixture, would that do it, remember I said the plugs were a nice light biscuit colour.....maybe a Vitesse needs builders tea colour!!