Tony at Turbo Systems or Karl Norris or MSD are all good Weber mappers, greys are a pretty dated injector now, ( they do their job mind) but there are better injectors around, power around 440-450 they start maxing out.

It would be wise to go and get it all setup, fueling, cold start etc, live map if funds allow are around 400-500 quid iirc.

Hope this helps