So I've been offered a 1671B regrind cam, believe it's for an AU, I want to know if it will work in my ED XR6 Tickford head ? And if so what if anything do I need to make it work ?

Thanks, Josh

From memory, to use an AU cam, you will need to replace the whole rocker assembly with an AU one. Since it is a regrind you will also need an extra set of shims for each rocker arm. If you have a self serve wreckers, you can grab an AU rocker assembly for $50 or so...well that's the price for the one at my local Pick-a-Part. You won't need to buy extra shims if you use the shims from the ED rocker assembly and you're set to go.

Check the ED shims first. Some have the larger earlier shims, 14mm (EA/EB) while the later ones were smaller, 11mm (EF/EL/AU). ED got a bit of a mixture depending on the manufacture date.