Im guessing you do alot of work moving around and involving your arms as a labour?
I would limit your workouts to 3/week. Stuff isolation movements, you want to get big you can cut them out.
IMO i would run something like this:
monday: chest+ tris+ shoulders
tues: break
wednesday: back + bi's
thurs: break
fir: Legs
I would do 2 excercises-no more than 3 per muscle goup @ 3 sets each excercise.
IE;
Chest, tris, shoulders:
DB bench 12,10,8
flys 12,10,8
shoulder press 12,10,8
delt raise 12,10,8
scull crush 12,10,8
tri push down 12,10,8
breaking up your groups like this will ofcourse make them a litttle longer, but limiting your excercises should put the time frame back in ok.Still try to keep your workouts consistant but do not rush them to a point.Dont train longer than 1.5 hours, and if you find you are get on the creatine and make sure your getting enough amino acids in daily.This is perfect imo, its not undertraining but its not breaking the overtraining barrier.which in your case, overtraining would be more of an issue due to work.
And remember, keep eating!