will a 352or 390 fe big block fit in a 66 ranchero

 

Pardon my confusion, but isn't the '66 still the Falcon front end? If so, no it won't fit without cutting the spring/shock towers.

In the day, I remember a guy complaining about the light weight front end under his '67 390. Not being able to maintain front end alignment was the issue.

300 more pounds on the front end is almost always a bad thing.