Generator & transfer switch install


I had a discussion with a co worker about a new install of a generaor transfer switch installed in a existing residential home , I believe the transfer switch which has a 200 amp main s now the service disconnect for the residence which would mean that the existing panel would have to be sub fed & the existing branch Circuit neutral conductors and equipment grounding conductors would now be isolated and also the cold water bond and grounding electrode conductors should be moved to the new transfer switch. Would this be correct install ?