hi would anyone know the whereabouts of the oil pressure switch on a Leyland 400 fitted to a Bedford tk,
Have you chekced the obvious, oil filter housing or the side of the block?
yes tried that, a local lad said he thought if fitted in a Leyland it would have had a gauge not a light, and the cab on this tk is not original so no big hole in the dash, there are two switch type fittings at the compressor, but they do not appear to work, I did suggest that they try both as if one was air pressure that’s not going off until the air pressure reaches 50 to 60 psi even leylands cannot get that much oil pressure,
I will try and ask my mate when next on shift as hes old enough to have worked on Leylands 
It might be worth a look around t’other side of the engine. I haven’t found a picture with an oil pressure switch on a 400 or 600 near the oil filter so far. Although this is a 600 engine the 350/375 and 600 were all designed around the same time, the architecture is similar but not identical. There is definitely an oil gallery on the o/s side of the 600 since some versions have the water pump on that side and it requires an oil feed. I have had to make a new pipe for it in the past. It should be easy enough to see in a TK although it might be behind the gear linkage.