For the big plate weight workouts, stick with universal-style machines that use plate weights if you're solo - the kinds that have lock-out bars to save you in case you fail right out.
For legs, I use seated incline leg press with plate weights (as above) and inclined hack squat as a substitution for pure squats as I don't like to tie up other people when I do my workout.
Also, for bench press in 3.1 I've subbed in universal-stacked weight bench press for barbell press. The individual handles also swivel some and allow me to squeeze more at the PCP I find. Perhaps it's mental. But it works for me.

I love doing my hack squats and then inclined leg press... you'd think you're smoked after the first and unable to make gains on the second. I've gained for 4 weeks out of 4 in doing it. Week 5 is this week for me.
Gotta love TA 3.1.

A Canadian MuscleHack enthusiast from North Bay, ON.
Blogging about my experience and all other MuscleHack-related stuff at
Rep to Failure.