Only one such set was built and it is now based at the Lappa Valley Railway near Newquay in Cornwall. The 7¼-inch gauge miniature woodland railway is approximately one-fifth of a mile long and is a circular ride running through a tunnel, round the Trevithick maze, past the nature pond and back to the main station area at East Wheal Rose.
Original Mardyke APT-P 7¼" at East Tilbury Coalhouse Fort 20 April 1984, Photographed by Keith Gunner.
Later modified to have a powered driving trailer rather than central power car and now at the Lappa Valley Railway.
Mardyke Miniature APT-P at the Lappa Valley Railway filmed by Paul Leadley August 2014.
If you have any pictures of this train in action - Please let me know !