I have a G Gauge loco called lynn from the Lynton Barnstaple namesake. My problem is that the loco has knuckle couplings, but the L & B coaching stock are all chopper couplings. Is it possible to replace the knuckle couplings for chopper types, and how is it done. The coach chopper couplings are just screwed to a thin metal strip attached to the wheel bogies. Any ideas please. Croffer.