Personally, I think bikes of a certain age, like this (or up to 1990 ish), look a little wrong/weird with forks, but then if it's getting used go for it. Can always change it back, but be prepared that I reckon 90% of people here will say no !
Thanks both, that's really useful. More food for thought.
Have just agreed to take in a stray 88 22" Saracen that will satisfy my need for fiddling for now.
This, the pioneer, rides really well as is. I suppose it would completely change the characteristics and upset the alchemy of the original build as it was bespoke for the previous owner who is my size and weight.