Supershredder, I feel your pain, bro. I have done everything from ditch digging, to land demolition, to warehouse work and even a little framing. My suggestion would be to follow a routine like:
Day 1:
Bench press (BB or DB)-warm-up, 2 working sets 6-8
Incline bench press(BB or DB)-2X6-8
DB flyes-2X10
pushdowns-2X10
DB or BB ext.-2X10
BB curls-2X8
hammer curls-2X10
Day 2:
pull-ups-4 sets to failure
BB rows-2X6-8
DB rows-2X6-8
military press (BB or DB)-2X10
side raises-2X10
bent-over raises-2X10
Day 3:
squats-warm-up, 2 working sets of 10
leg press-2X10
leg ext.-2X10
lying leg curls-2X10
calf raises-2X15
seated calf raises-2X15
I would recommend the low-volume, because I think its the best overall strategy, but also because it will enable you to have adequate recovery because of the physical labor that you are doing all day.
I also excluded deadlifts, upped the reps for legs/delts, and lessened the biceps/forearms exercises because theses movements/muscles are what you use all day long at work.
Time, being any issue, I would recommend resting 90 seconds between sets. You also do not need cardio because of your work. Good luck.