As a highschool kid that didn't tip the scales over 150 at the time, I used to grab the gear shift lever and remove the last top bolt from the transmission to flywheel housing, and lower the transmission to the ground. On a half ton 57, yes and also put it in the same way. Yeah the trans weighed about what I did. So it can be done without a jack.
LOL
We all did dumb things as kids. I used to carry around bare Model A blocks. My back is worse for doing that, and I was a big kid (6'3" and 180 lb). I recall that my dad once bench pressed the 4-speed tranny out of his '48 GMC shop truck when it needed fixing.
