The stock 490R is a pretty low output, AII PAF style pickup and I think it sounds OK. The 498T bridge is much hotter and doesn't work particularly well in an SG.
(Having said that, about 10 years ago I had a Korg Pandora PX1 with a "Schenk" preset, and the only guitar which actually gave me a reasonably authentic Schenker tone (IMO) was my SG Standard with a 498T. But that's completely irrelevant.)