Z1OwnersClub GB

Hi
My latest purchase has I believe either Z1B or Z900 engine fitted, is there anyone who can confirm this for me.
Engine number is:
Z1E062467
It’s supposed to have a 1015 mk2 style engine, it still has the accelerator pump style carbs which I think were on the 1015 motor.

1975 Z1B motor I think.
Carbs should be 28mm pumpers for the US 1015c ltd.
These can be identified by only having the square pumper diaphragm operational.
The casting for the triangular one next to it should be unmachined with no cap.

z1b motor

Thank you guys, I’ve worked on Z1B engines before, nice to know what I’m dealing with.
Removed all precious bits today (tank/panels & seat) before it’s removed from the shed it’s been living in.
Tank is lovely with no dents, clearly been painted as its Z900 green but is rather rusty inside which I’ll have to address.