When I'm working on really heavy stuff like my tractor or any kind of tracked vehicle, I use crisscrossed layers of timber similar to railroad ties for support. They give a bigger footprint and better weight distribution than stands. a stovebolt sized truck should be plenty safe with jack stands, but the wider the base and the heavier the weight rating, the better.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!