Hi Steve,
Yes there is a sketch of how to make a dummy engine cover in the T2 manual. Hopefully attached is a picture of mine. I made a dummy radiator and used the Toylander bonnet catch screw to locate into it to lock it down. Underneath is hidden the High/low (4/8mph switch) and the remote control on/off switch and as you say the delicate electrics.
I got my idea for the engine from the best one I have seen on here which was made by sub6666, if you can search for that. I had to cut down the jubilee clips to make them smaller for battery connections. Am looking out for a dishwasher hose to connect the airfilter (Bisto gravy packet painted white) to the carburettor.
Regards
Mike