Result !!
After a little headscratching, the change from cassette player to CD player went very well. I got the Jazz CD player from a Japanese car breaker in Oldham for £100, and following your advice, obtained the aerial adaptor from Blue Spot. The only difficult part of the operation was re-routing the air conditioning wires. However, a beautiful factory-fit CD player is now working well, at a fraction of the price you would have to pay a Honda dealer, or car audio specialist. Many thanks to “lanciauk” for all your valuable advice.