Useful thread, thanks, I've now ordered some Infinity 5022i 13cm (5.25") speakers for the front doors.
Left with my old 16cm (6.5") Infinity 6522i speakers, which had from my old car.. failed attempting to get them to fit in my Puma front doors. Be nice if they fitted in the rear with an adapter... will look into possibly making an adapter up for them before selling them on.