My memory is good, but short.
My brain has got too much alu?
I thought that the square box in the middle was the pump.
But when I check mine they look the same. Except for a little bit tighter, cut and welded to use OEM carb boots.
I guess I was tired jetting them, replaced them with TMR32's. VM29 will fit my spare parts, soon complete engine.
I have read about acc pump on VM29. Here a link with 2:nd photo with a strange device under the float bowls
http://www.redlinecycle.com/Carbs%20-%20VM29.html