Glad to help-keeps the ole' brain workin! I'm gonna take a guess based on old Hysters I used to work on how they were hyd plumed. I'm guessing the aluminum box you speak of is a diverter valve of sorts- controlling the flow of oil to the bell housing. Check for broken springs, sticking valves etc in this box (if I'm right).

I agree the hoses w/ no clamps would be the low pressure returns. I would also check these for blockage.

How are the hydraulics- do they have a "normal" feel or do they seem weak & sluggish?