The wire coming from the gray strip(Neg) goes to the "Battery -" tab. The other wire goes to the "M/B +" tab. Neither wire should contact the center tab.
I hope this is what you needed.
PM me your email address, and I can send you the V12 Manual. Its a .pdf file so you will need Adobe Acrobat reader though.
TLR 22...Tamiya F104...