383 Into Stock Slant Six K Member?

Since no one else has make this comment, I noticed you said "66". You don't have a k frame option. There was no "big block" k frame for 66.

The 67-76 A body was redesigned with a larger engine compartment and different K frame designs.

The 63-66 used the same k frame for either the /6 or the small block V8 (with different mounts). There was no big block option in 66. The newer k frames will not work on that application.

Schumacher Creative services http://engine-swaps.com offers a conversion mount for that k frame but the big block is a VERY tight fit in the earlier 66 engine compartments. All of the above posts about the 383/400 being narrower than the 413/426w/440 are correct. You get about 1/4 inch which is a GIFT on that swap! The 67-76 A body swap is much easier.

As far as handling the weight, what you want are larger TORSION BARS. I believe the aftermarket bars will fit in the 64-66 A bodies.

Good luck!
Greg Purcell