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Help With T56 Magnum Swap Wiring

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Hi all, I'm working on my T56 Magnum XL swap in my 2011 Mustang GT HPDE car and am a bit unsure how to proceed, wiring-wise. The swap came with a few pigtails but I decided to go ahead and obtain a Bowler All-in-One harness and installing that is my next step. My questions amount to how to handle the reverse light wiring splicing and where to go for 12v switched power, plus clean ground. Couldn't find much while searching online and on YouTube, apart from one video on YouTube where the fella seems to be splicing into the 12v coming from the ECU to the original MT82 and the ground wire in that harness as well - I understand that's a big no no for purposes of wiring something like the Bowler unit (which is also powering reverse lockout solenoid, etc.).

So, my unsophisticated self currently is thinking of running the Bowler red 12v wire out to the fuse box in the passenger footwell to a 12v switched unused slot (add-a-circuit) and use a ground bolt there as well. Thoughts? As for the VSS signal wire, the Bowler instructions indicate which wire from the factory harness provides that signal, so I'll need to dig for that in the factory transmission wiring harness and splice. And that should leave the two Bowler reverse light wires. Apparently one goes to 12v switched and the other goes to reverse light signal? No idea where to take those two wires.

Any thoughts? Might benefit from a phone call with one of you guys to bottom out on some of this stuff! Appreciate your time!
 
1,119
1,110
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
I did mine a few months ago, but didn't use the Bowler harness. I used pigtails from Modern Driveline. My tuner changed the gear ratios and VSS setting using HP tuners. I did need a ground and switched 12v source for the reverse lock out solenoid. It took some searching, but I found both in the console. It took awhile poking around with a volt meter to find the switched hot, but I found it. I don't remember the color of the wire, but could pull the console and snap a couple of pics later this week if it helps.
 
1,119
1,110
Exp. Type
HPDE
Exp. Level
5-10 Years
Lenoir City TN
If I am remembering correctly the switched hot I located was an unused plug that powers the gear shift selector indicator on automatic cars. I think it was a 2 wire plug with a hot and a ground but I don't remember the colors without looking at it or a wiring diagram again.
 
If you utilized the automatic transmission selector plug (included but unused in manual cars), I actually have ref pics and wiring diagrams of that one. See below:

DimmerIlluminationAnd12VPower-UnusedAutomaticShifterConnector4.jpg
DimmerIlluminationAnd12VPower-UnusedAutomaticShifterConnector5.jpg

DimmerIlluminationAnd12VPower-UnusedAutomaticShifterConnector.png

If you want to get the other side of the plug that would be on the transmission selector assembly in order to add some pins and make a clean install without chopping, I believe the part number is WPT-1299 / 3U2Z-14S411-NBB.
 

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