Fj60 Ls swap wiring questions

[georgiacruiser87]

I recently pulled my engine and am cleaning up the engine bag. I’ve got the driver side tidied up and am now on to the passenger side body harness.

I’m probably getting ahead of my self, but I’m trying to make sure I’m 100% ready when it’s time to put the Ls in.

So far

Obvious keep:

Headlight
Turn signal
Side running light
Oil pressure sensor
Ac on wire

definitely getting rid of:
Ignition coil wiring
Alternator wiring
Evap canister had a plug connected near it?

What’s confusing me:
Trans and transfer case had electrical connectors. I’m assuming these are simple switches to the 4wd light in the dash and the trans to the rear reverse lights.

This 60 had a starter button with a wire running all the way around to the fusable link then to the starter I believe.

And fusible link itself. I’m assuming this runs power to the fuse box. Should I keep it and just run it to the secondary positive on my battery or run these power wires to my battery via the new gm positive with fuse.

Pics to follow tomorrow.

 

[cruisermatt]

Don’t get rid of your original alternator charge wire, you want to use that as it feeds the majority of the original fuse block with constant +12v.
What engine and transmission are you using? If staying manual you shouldn’t modify the transmission sub harness at all.

What are you using for your LS engine harness?

Yes, you should keep the fusible link if some sort.

 

[georgiacruiser87]

6.0 with 6l90e with a bpa harness. I have the original harness from the donor truck as well just in case I needed anything from it.

 

[cruisermatt]

there isn’t really much information about 6L80/90 on this forum.
You want to get one of these for the NSS and reverse light function unless you are using a shifter with wiring functionality built-in

10L90 NSS Module

Speartech's 10L80/10L90 neutral safety module provides an easy to install neutral safety switch for your swap application. The module also provides an optional reverse light output for backup lamps and/or reverse light cameras!

www.speartech.com

 

[BurntToast]

I recently pulled my engine and am cleaning up the engine bag. I’ve got the driver side tidied up and am now on to the passenger side body harness.

I’m probably getting ahead of my self, but I’m trying to make sure I’m 100% ready when it’s time to put the Ls in.

So far

Obvious keep:

Headlight
Turn signal
Side running light
Oil pressure sensor
Ac on wire

definitely getting rid of:
Ignition coil wiring
Alternator wiring
Evap canister had a plug connected near it?

What’s confusing me:
Trans and transfer case had electrical connectors. I’m assuming these are simple switches to the 4wd light in the dash and the trans to the rear reverse lights.

This 60 had a starter button with a wire running all the way around to the fusible link then to the starter I believe.

And fusible link itself. I’m assuming this runs power to the fuse box. Should I keep it and just run it to the secondary positive on my battery or run these power wires to my battery via the new gm positive with fuse.

Pics to follow tomorrow.

I did a 6.0 with 6L80 into mine, keep all the stuff coming out of the driver firewall. Basically all the stuff coming from the computer can go. Keep the starter wire, you'll mate it to the new starter.

Keep the tcase switches/wires.

You can keep the fusible links like Matt said, or do something different and move to real fuses like I did. Pros and cons.

I jerry rigged a lokar NSS lever switch to act as reverse switch for my reverse lights. My lokar shifter had NSS built in.

 

[georgiacruiser87]

Matt can I remove the two wires that are tied to the alternate charge wire with this setup? Some quick research shows that those 2 are used with the 4 prong plug for the alt on the Ls alternator, but the alternator I have is a 2 prong plug? I think one runs to the light and the other is an exciter. Could these be tied in with the two prong plug?