Im not sure, if I understand your question correct. BUT i think i do.
Heres is how my MSD TL i wired. From the battery i run a big 12v+ (positive) up to the enclosure, on the starter solenoid. From this post i have attached my MSD 12V+ (positive) wire.
I run a big 12V- (negative) from the battery to the alu plate, that mounts everything in the elcosure. Heres are all the ground/earth/negative connected.
I allso run te MSD module, that sleeps and wake up when the lanyard is connected/disconnnected, this is allso mounted in the enclosure. This way i avoid running the red, black and the violet wire outside the enclosure.
Hopes this helps?