Does anyone know if there is any software readily available that allows you to remap cossie ECUs? Costs?

I've been thinking of returning to the Cossie world for a while now, probably with a 4x4 Saph but would like to tinker about with the mapping side of things if I do.

I've found a bit of info about L6 & L8 ecus - map locaions etc and could write software to edit the maps myself if I had to, but just thought someone might have already done this sort of thing before?