What, if any, differences are there between the 1966 and 1967 Skylarks as far as wiring. I'm basically wondering about low optioned 300 v8 Sport Coupes. I'm wondering, since I am going to replace all the wiring in the car(my 66 with a 455 transplant) from front to rear, would there be an issue just ordering the complete harnesses for a 66 GS400 since the block size is the same as the 455? Big assumption is that the gauges, switches, connectors, etc. stayed the same between the 2 yrs. I'm also assuming I can't just plug in the 67 GS400 engine harness to the 66 bulkhead connector, which is why I'm asking if just buying the complete wiring setup for the 67 is doable? Does anybody know for sure? Or buy the 67 GS400 engine harness(because if it's extra length over the 66 300 engine harness) and change the pinouts to match the 66 bulkhead connector(if those were the same?) Didn't like that when my car was running last, that the 300 engine harness was too short for the 455 and not routed correctly. Would like to hear others opinions on this. Thanks!
When I installed a 455 in my '64 I ordered a replacement engine harness for a '64 300 and it worked just fine with some minor adjustments. Rather than convert a '67 400 harness I'd order an engine harness for a '66 300 and work with that. All other wiring harnesses should be for a '66 too. A '66 GS400 used a Nailhead engine so you'd probably end up making more adjustments that you would with a '66 300 harness, since the distributor is in the rear of that engine and the starter is on the driver side.
What adjustments did you have to do? When mine(455) was running last with the 300 harness, I had to unclip the harness from the firewall and move it forward and basically leave it hanging. It just needed a little "stretching" but didn't leave a lot of slack like down around the starter. It was just a little short everywhere. It just made changing the starter a PITA because there wasn't enough slack. My thought on the 67 GS400 harness, since the motor is the same physical size and arrangement(alt/starter/distributor,etc), is to get the 67 GS400 harness and pop the wires/pins out of the bulkhead connector and move them to the 66 300 configuration(if different?). Other than that modification, I really wouldn't need to do anything else. Or am I wrong? I just don't want to get a new 300 harness and then have to hack it up to lengthen wires. Edit...added... I hope my questions aren't coming across as if I'm being argumentative. I'm not, I'm just asking questions and in my mind, maybe thinking outside the box to what I think is a small problem. Any answers or responses are greatly appreciated and hopefully I'll learn something. Thanks!
