There must be surplus Cessna T-37 trainers available for civilians.
Here's what I would try
Take out the ejection seats to save weight.
Add 6 ft to each wingtip (there's a huge stabilizer on this airplane, so it would be stable)

When finished, take off and head out over the mountians and get into wave lift.
One engine throttled back would be enough for staying in the lift zone.
I dont think this is wacko because the T-37 is a very clean airplane
A P38 once flew in wave lift