Exploded cooler fan and transmission fuild

Context: cooler fan exploded becuase of a bearing, it shot shrapnel into the radiator hookups, the transmission line was destroyed, and now I wonder how once I replace the line know how much transmission fluid to put in?

2007 sprinter diesel

there is a after market dip stick you can buy check e bay,i can not find mine to get a part number or add fluid to get it to move and have it flush at a fast lube place they will had the dip stick i do not flush transmission no more as that they can do it cheaper