Will a 66 drivetrain swap in to my 68??

The Doug's headers will not fit. Not sure about the rest of the exhaust system. I have first dibs on the headers for my D/Dart. And maybe the wiring harness.

With Yukon Axles, I'd assume it's an 8 3/4 and it should bolt right in. I'd take the upper control arms and the spindles and put them on the 68 as an assembly. The lower control arms are the same. If they have all new bushings in them, you might as well swap them over too.

While you have it apart, put in all new brake lines on the 68. I believe the 66's are different. Also new fuel lines.

You should be able to find a set of 67 up V8 motor mounts.

Good luck with the build