What model, and how many axles?
If it is a single axle, the running gear may be ok if the interior modifications didn't add appreciable weight. Depends a lot on how well the previous owners maintained the brakes and bearings. I wouldn't tow it without checking the brakes, tires, and bearings.
I have replaced the axle in my '59 Tradewind, but I plan to add a lot of new upgrades, like a graywater tank, A/C, batteries. I believe the original single axle tradewind had an axle rated at 3500#, and the dry weight was 3160#, not much margin for food and clothing.
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