Steven Van Dyck
Didn't you also get a transmission box? I have a few of these. There was a time when all Tamiya models had a little engine, not for RC but just on/off...

Chris Harbour Author
No, that was not in the box. I have had a search and got a bunch of brass etching, cranes and handrails etc. but did not come across anything like that. And the instructions just show gluing in plastic ones.

Any idea where i can get one from?

Kesa Tiho
Same thing with mine, my guess is that you can also use it to store the batteries for led lights youd place into the ship itself.
If @Steven Van Dyck is wrong then it's just lost to time.

Steven Van Dyck
Check the timeline of this kit, it goes back to 1978. They even sold an engine apart from the kit then, but now that's out of fashion or even considered unsafe to have kids tinker around with 4 batteries in selfmade circuits that can get waterlogged and they leave out all electric components. You would have to look at that original kit to have them, I don't think they are that rare to find.

Check step 3 of the manual for the engine nstallation. scalemates.com/products/img/2/0/1/121201-91-instructions.pdf