Can't find out much about this aircraft so I guess it might not have been a success. I would think that this aircraft would be the last aircraft to roll off a production line at Luton even though it was technically a conversion.
The first McAlpine conversion to Riley Executive 400 standard was completed by mid-1965.
The Riley Executive 400 conversion was available from Riley and McAlpine in six stages, any one of which could be taken on its own if the customer did not want a complete conversion:
1. Re-engining with two 400 hp Lycoming IO-720 eight-cylinder horizontally-opposed air-cooled engines, each fitted with two Riley Turbo 300 turbo-superchargers and driving a Hartzell three-blade propeller. New sweptback vertical tail surfaces and a "fatigue-free" steel spar capped wing were included in this stage of the conversion, which contributed 90% of the overall speed increase and 90% of the weight decrease of 800 lb (363 kg) offered by the conversion.
2. Remanufacture of the flight deck to include one-piece instrument panel and improvements in field of vision.
3. Flush riveting of entire wing from leading-edge back to rear spar and epoxy coating of leading-edge.
4. Replacement of existing cabin door by air-stair door.
5. Complete cabin re-styling, with improved sound-proofing and installation of fully-reclining individual chairs.
6. Removal of all existing paint and refinishing with epoxy resin paints to customer's specification.