I am in contact with some American 00 enthusiasts about this model and they are asking if it would be possible to convert the model to 19mm gauge. I presume it will be convertable to EM or P4, if so it should be possible to convert to 19mm.
There was also Walford Arches that used the Faller system. Regrettably the guy who built the layout has passed away but I have heard that the layout still exists.
That would be the Falklands, the mines were laid by the Argentinians. Where as an adult human would set a mine off the penguins are too small to explode the mines. In fact they have prospered due to the lack of human interference.
What's next? Seriously as you already have the mechanism what about a Sentinel articulated railcar? At least 3 different LNER liveries, LMS and both lines on Jersey so thats 6 livery options to start with.
On the subject of the Fordson/Muir-Hill shunters the one illustrated in Railway Bylines was one of a batch delivered in 1959 based on the 'Power Major' model. I have a booklet about Muir-Hill products and in there is a photograph of one from the same batch numbered 755 X0 M, this one does not have the shunters platform giving more room for the number so that the 'M' is placed below the rest of the number. There is also a photo of a slightly earlier one (1954) numbered RW8106 N the differences are that the number is in one line ahead of the shunters platform and a different style of cab with a vertical windscreen and what looks like a canvas roof with unglazed sides with roll down canvas weather shields. The roof is quite deep with sharply curved corners like a Land Rover hardtop.
Also they had a tendancy to change from rail to road mode en route and vice versa. I saw at one time a photograph of two gouges in a tarmac road where one had 'swapped mode' when behind a lorry! IIRC in every case the locking system was not applied properly.
On another thread 'Tonight Merlin, will die' at the start of the film a ramp wagon in use is visible in the background. It starts at around 2.26 and note the improvised 'railway crane', a Ruston Bycrus on a warflat.
There is a brief glimpse of a roadrailer 'in action' in one of the Pathe newsreel films. IIRC it is the one featuring the building of the flyovers at Barking in the early 1960's'. The train consisted of a class 24, an LMS parcels coach and and the adapter bogie with two roadrailer vans.
The unmade kit will probably be worth something to a collector but 'made up' models are not worth a lot. I recently purchased a made up tractor unit and two trailers together with a pair of made up Airfix lorries all for a fiver. There was also on the vendors stall one of the trailers converted to a OO9 van.
The 'cage' on the side between the wheels is a platform for the shunter to stand. I have never seen one where the shunter ever used the platform however.
This is one of the Muir-Hill ones. It appears that the bonnet/grill has been replaced at some time as they were usually in all over yellow. The earlier ones were in BR 'blood and custard'.
The body was from the Siddely-Deasy railcar. It has been rescued for preservation and I understand that it is hoped that it will be restored as a railcar possibly with a replica chassis.