I have two 1989 Firebirds. One was previously a 305 5-speed. It has a nice, rust-free body with decent paint, and no drivetrain. The other car was full of rust, but had a running, driving 305 auto. I've swapped the drivetrain from the donor vehicle, into the car with the decent body. I've added a cap over the large hole in the trans tunnel, and mounted the shifter. Ive also swapped the pedals. I think I have everything complete, witht he exception of the wiring for the shifter, neutral lock-out, and reverse lights. Please advise how I should go about connecting this.

Here's the connector, that was previously attached to the shifter, in the donor vehicle


Here are the wire connectors from the donor vehicle, under the driver footwell:


On the car that was previously a 5-speed car, I have these wires left over, under the driver foot area. There's also a white one at the top of the picture, facing the camera:


I also have this, coming from the shifter:


Any advice on how to complete this swap?

 

In the picture that shows the fuses, the connector in your left hand is likely for the clutch pedal safety switch (PRP & GRN wires). If so just jumper the two wires together, that is what GM did. Could get the jumper from the donor vehicle.

The first picture as you mention goes to the switch on the auto shifter. The two big wires are the P/N safety. The other wires are for the backup lights and P/N input to the ECM. With the BLK/WHT wire going to ground.

RBob.

 

So, the 6-wire connector in the first pic. I need to just cut that out of the donor car. What am I splicing into the larger purple and green wires on this connector?

 

So I pulled out my 1989 Camaro service manual (I guess it's probably close enough, for what I'm wiring up). Before I cut things up, am I on the right track?

Black – Ground – goes to ECM (Other things are attached to this ground - should I just ground to the trans tunnel?)
Orange – Neutral/park – goes to ECM - snip orange wire at ECM, jump to orange wire at shifter
Blue – goes to ECM - - snip blue wire at ECM, jump to blue wire at shifter



LightGreen – Reverse lights - have not found this wire yet?

HEAVY gauge DarkGreen w/ white stripe – This is behind the driver kick panel - snip green/white wire at kick panel, connect green/white wire from shifter to black box (what is this box?)


HEAVY gauge Purple – This is behind the driver kick panel - snip purple wire at kick panel, connect purple wire from shifter to purple/white wire

 

Any thoughts before I do this?
Feedback appreciated.
I'd rather know now that I am totally wrong, before I burn my car to a crisp.

Thanks in advance.

 

Depending on how far you are taking the the car apart but is it a possible to just swap the complete harness to the one your keeping?

 

On the T5 the reverse light switch is on the transmission.

RBob.

 

I'll be honest, I've not tinkered with the interior wiring before this project. I assumed it would be like the under-hood wiring, where there are separate harnesses for the lighting, engine, etc. I thought I could replace a harness or two, and since I have a donor car on hand, it would be no big deal.
But that's not really the case. There is one huge mass of wires. It would be a massive undertaking to redo the interior harness, and based on the small number of wires that I really need to jump, I think it's 100x safer to just re-wire these few wires.

I keep studying wiring diagrams, and I think was incorrect with the blue wire. That's not going to the ECM, it's coming fuse panel. Since it's powering a few other things in addition to the reverse lights, I'll probably just send a 12v wire to the blue at the shifter. The others, I'm feeling pretty good about. I'm going to pick up a new battery tonight, do the wiring tomorrow, and see if I can finally start this car up. It's been almost three years since I bought the pair of cars, so I'm really anxious to get moving on it.

 

Found it, thanks. Looks like it goes through the C100 bulkhead, and runs down inner driver side door trim. I can grab it under the dash, before it goes into that cluster of wires.

Bought a new battery tonight. Should not take long tomorrow to find out if I am totally wrong.

 

Well, car turns over, so I guess that's progress. Would not start, no spray from injectors. Popped the cap off, and found this.
This engine ran, when I removed it from the donor car.
Is this just an old distributor, experiencing catastrophic failure? I've got another old distributor, from a TPI car. So I think I'll swap that in.