Agreed, Algar Ferrari. I've dealt with Ryan quite a bit over there. Depending on where in the Philadelphia area you are, Wil at Exoticars in Frenchtown, NJ is also a good bet. Exoticars has performed routine maint on my 360 and they are also very good and thorough. Quite advanced for an independent IMO. Wil opened the shop on a Sunday for me to visit because I was in the area which I thought was a plus on the customer service side. Some of the bodywork and restorations he has going are amazing.
I would recommend either one for sure. I would just ask about expertise with the 355.