Be careful with this one Guys. Yes It may well be a sheerline 6 on a model 8 base,as it seems to be a Sheerline head in the Images. My assumption is the same as All of yours.

The STD did come with the sheerline style cowl setup and ran in and around the same time as the Sheerlines,but it ran the 8A engine on the model 8 Chassis.

Anyways this having what seems to be a sheerline head and possibly engine would definately make it incorrect. Close But,Not quite Sir!

Having said he has never seen one before kind of makes sense...I have never seen a STD either in real life. But he has his models mixed up as well as the terminology...MK3? No such thing!:)

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