[Macoozie]

1968 Ford put 302’s in instead of 289’s. A 302 into a 66 would require motor mounts and much more. Really a silly thing to do.
The 289 was(is) a much groovier deal.

Weird article.
Yes I’ve had quite a few over the last 60 years.

[John Milner]

I think if you wanted the small block 4V you got a 302.

But pretty sure the 289 was still available in ‘68 with the 2 barrel carb.

[Clay Moore]

The 289 and 302 were interchangeable except for the some of the very early 289’s which had a 5 bolt bell housing (like the 260) instead of the later 6 bolt.

The 302 came out mid year 1968.

[BubbaBasher]

A 302 into a 66 would require motor mounts and much more.

Incorrect. The 289 and the 302 are physically the same on the outside. The bolt pattern for the exhaust is the same. Both are interchangeable as well as the 351W. I've even swapped a 351C into a 289/302 engine bay without problem.