[JimC]

I'm looking at a pre-73 Skymaster that's about 250lbs over the "factory" weight. It's got a 400 autopilot, old radios, Robertson STOL but nothing obvious. Is this common? Can I reasonably expect to put the plane on a diet (modern avionics, rewire, etc) and get 150-200lbs back?

It's a 337D. Factory published weight is 2655, this one is near 2900.