No, the cost for skimming, lapping in new valves, new valve stem seals and labour came to around £2 - 2.5K. As I had new spark-plugs, timing belt and tensioner, thermostat, radiator, fan and coupler and service done the final bill, including all the associated costs came to around £3.5 - 4.0K.
The £4.5K total I gave earlier was off the top of my head - I've since checked all the invoices. My Bad! 2-2.5 is realistic if your head's warped.
Mind-you - further to that I am still not satisfied the HG is correct, as I have a gurgling dash and what looks like over-pressure in the coolant system. After talking it through with Chris Wilson, it might be cheaper to get a 2nd hand engine rather than try to sort it out as the heads are very sensitive.
Approach with care and get good advice!