This takes me back! However if you want a rack mounted seat you are going to have to buy either a specially made carrier or a disc brake mount adaptor. I have seem these, not sure where but probablly at St John St cycles. You could also check out Spa cycles at Harrogate. Either way you will need a specialist touring dealer. I believe the adaptors work by elevating the base of the carrier, which might give stability problems as your child grows and gets heavier. With the carriers you may find your seat doesn't fit. I guess that the best option is to return your seat and try and find one with a different fitting system.

Thanks for the advice guys. My LBS reckon that they may be able to fit the rack for me but i have my doubts to be honest. They may be able to fit it but whether it will be able to hiold my dausgther is another matter. She is a bit of a chunky monkey nad it I want it to be safe.

If they cannot fit it then the Hamax it will be. I had my reservations about the Hamax seats but your recommendations have changed my mind.

Once again thanks.