Basing the Viewliners in Sunnyside doesn't make much sense, space is at a premium there already. Building a facility there for the Viewliners would be extremely expensive and wouldn't be a good use of time or resources. The heavy maintenance for Amfleets and Acelas is in Delaware, the Superliners and Horizons in Beech Grove, and the Viewliners in Miami, all locations where land is relatively cheap. The majority of the time when a car is due for PM they'll cycle it out from the LSL or Cardinal set and into a Silver Service set (with its replacement coming from Silver Service) so that it can be cut out when it gets to Miami. The only train where you'd have to deadhead something presently is the Boston side of the LSL, and that should be able to be avoided by swapping it in Chicago.