thats why i wanna put it in the bilge. on the "battery shelf", if you mean the boxes in the aft, port and stbd, it will need to be pulled out to add oil. in the bilge i can arange it so that when i open the bilge access hatch it will be right there. just unscrew the cap and poor it in. frees up more space above deck and theres plenty of room in the bilge for it. wont be in the way at all.
i know its never the best idea to put screws into the stringers but mine are seacast plus i will pre drill and dip my screws in resin. only thing that concerns me a little is that it will be much lower than the motor. dont know if that might cause a problem?