Thats Good stuff Rowland! Very impressive indeed!
I would be very interested in doing this to my 450D...it's getting on a bit and new DSLRs are getting cheaper so if I kill it...no great catastrophe. I will go to a cooled CCD, someday, but I do find a DSLR an excellent all round camera. They are very clean noise wise with low sensor temps.
I reckon this would be a very worthwhile and rewarding project....PM sent.