question on dse power boxes

hi newbie here ,bought a p38 dse and chuffed to bits with it , had box of parts with it includeing a power box which last owner took off because of insurance . i want to fit this it has 2 plugs male and female which i found where they go but there is a single wire that goes somwhere is it an earth or a positive ? has anyone fitted one pls the box has no name

Look under the inlet manifold and you will see where a plug will remove from and you can plug in to the plug that you remove from that plug the other end of the box's loom in to

re the single wire

It goes on the presure sensor on the inner wing very neer the fuel filter housing (ON PIN 1 )
pull the rubber gator back and you will see that the plug is numberd

hope this helps m8 (note this is on most boxes i have fitted anyway) ME not responsible lol

ok cheers bud