[LS short box]

Maybe not for you but a local body shop painted parts for me one or two at a time. All were base coat clear coat solid colors. Materials are expensive so doing stuff twice gets expensive.
I would strip the body panels and take them to the body shop and they would epoxy prime them to keep flash rust away. Them I would store them away until body work time.
When all that was complete I again then body worked/block sanded each part as needed. Parts went back to the body shop for paint, wet sanding and buffing.