Have to say, I wouldn't really advise shuffling reeds around. Apart from problems with the reeds not properly fitting in the pan (which could cause problems for years to come) there is the fact that the reed chambers have an effect on the tuning, and of course once you start shuffling you have reeds in chambers that no longer match. More than half the value of a concertina is in its reeds, so take *very* good care of them.

Have a look at my Concertina FAQ site at www.concertina.info, where there is a list of makers and repairers who could take on this sort of job if required.

A useful technique I've found for getting a song accompaniment started is: once you have worked out the basic tune try pressing neighbouring buttons on the right hand to play parallel thirds. Then put in the odd button on the left hand to produce quite a full sound. I tried this on Shoals of Herring myself a while back, and it sounds quite effective.

Chris