I have a 66 inch mount airy roll top desk that I need to take roll top off to move. Need to know how it disassemble

On my roll top, the tambour fits into a routed slide in the upper portion. The upper is screwed to the bottom. On my right side, without drawers, the screws are under the ledge, while on the left side, I pull the drawers and can access the screws there. I'd look for some screws from the underside.