Perhaps I should add that this is my first loco build (excluding a couple of N gauge body kits).
The chassis has been complete for some time...
...and runs beautifully, even if I say so myself
Work on the body, however, had stalled, and I've only recently picked it up again...
The extra weight has been glued inside the tanks, you might just be able to make it out. There's room for more, but I don't want to overdo it...