I nearly did it, but had to pull out because of the hassles there would have been with the particular aircraft concerned. Take good advice and talk tot he relevant person at the CAA. While they do like to make problems where many of us don't think should be there, they are very open in telling you the likely problems you will face.
Also, you'll need a starter warning light. I have heard it is £2-3K for an uncomplictaed addition to the G-reg.