I was just wondering how you put a smoker unit in a Tamiya JS-2

You don't.

Believe it or not, there's little room in a JS-2 hull. With the rear gear boxes, speaker box and the forward location of the rotation motor, there's no way to stack the DMD/MFU. Barely room for the Rx once the battery is in. As is, the y connector needs to be eliminated, I can't imagine squeezing a smoker in there unless you lose the speaker enclosure.

I justed thought I'll ask to see if any had squeezed one in.

but thank you any ausf

If you find a way please post it. I am very curious how you would do it. I can't see an inch of space in my JS-2

just find one new Zealand or the net is the only problem