understand that panels spars are unique to a series of panels so retrofitting a summit panel would take a lot of work to voice right with the bottom end. Different efficiency, compliance and spacing of spares, mounting systems changes would be a huge challenge to fit. It is important to note that replacement panels are built with the same spar and bonding materials as the original so that it is the same speaker, otherwise you would end up who knows what. We do use more modern panel materials though so you would end up better than original in terms of lifespan.
