I've tried that. It's currently on a sheet metal workbench. I've slid it and it bends the sheet metal. I can lift the whole bench onto some moving dollies and wheel that over, then slide the lathe off, but the new bench is higher than the old one by about 3".
At 350 lbs. if your floor is smooth concrete 2 people (or one large one) should easily be able to slide it across the floor, no moving dollies needed. Once you have the old bench next to the new one just block up the old bench until it is just a bit higher than the new one and slide the lathe over.