I did almost the same with mine with the exception that I didn't glue one of the horses down until I was assembling the thing. This meant leaving a section of the base unsanded until the very end but the rest of it, along with one of the horses, was sanded and painted allowing the chariot to sit on top of the earth nicely. They're fiddly! Oh, and I didn't pin the crew in, they're just stuck onto the painted chariot once finished and so far they've stayed on.