Thanks for posting your results. So it looks like cylinders 1 and 2 are firing but 3 and 4 may not be. But cylinder 3 is clearly still getting fuel. Was there fuel at cylinder 4? I assume your 3B is from Canada and has an in-line pump - I have no experience with these, but in general it's very rare for injection pumps to be problematic. Although I have my doubts that two adjacent injectors suddenly went bad, it's easy to take them out and get them checked.
I have no experience of turbocharged 3Bs and am more familiar with the later non-Landcruiser B engines, so I defer to those who have more direct knowledge - perhaps broken crankshafts are some peculiarity of turbocharged 3Bs. But when Toyota turned the 3B into the turbocharged 13B-T, they reinforced the pistons, con-rods and cylinder heads (by way of being direct injection, they never turbocharged an indirect injection B engine like the 3B). The one thing they left alone was the cranshaft (late 1984 and on 3Bs and 13B-Ts have the same crankshaft). So it would seem surprising if 3Bs had a weakness for breaking cranks when turbocharged. However, empirical evidence may contradict this. There was one. let's say 'famous' turbo 3B rebuild on this site which appeared to be very well executed but was underlain by some very questionable post-mortem and engine building practices. That ended, if I remember correctly, in a broken crankshaft, and that may be fresh in people's minds.
Pulling the sump pan off is not a fun job with the engine in place, and it will really only tell you if the crank has snapped or if there is a smashed piston. Taking the cylinder head off is a more conventional alternative. It's a bit more work but will show you the valvetrain, pistons and, by turning the engine over with a bar or tapping the piston crowns with a hammer hamdle, whether all the pistons are connected to the crank. It's your choice though.
EO
Are you talking about me?