Im not sure if I will run it as yet may just leave it on the shelf but temptation may get the better of me.
All those holes are to allow you to place batteries across the chassis with a extra battery holder so you had choice for battery down middle or across chassis...... You will notice as well you can fit batteries across the chassis in 2 stages back and forward.
I used to run speedo on left of car if sat in it, then wires straight through on to motor. Receiver on right if sat in it with wire from speedo straight across under battery with electrical tape over wire for protection.
I used to fit speedo and receiver nearer front so in normal condition run battery down center (dry) then wet fit battery across as close to the back as poss.
Hope that helps.
