Are all la 318's drilled for a pilot bushing

Talking about 60s to 80s 318 motors.

NO, they are NOT

Definitely NOT, those bushings cost money and time to installed them
None of the car factory have put parts in a motor or car that are not needed for a long, long time

And a warning, even if it's drilled, it may not be finished to the correct size. Or even centered.

Easiest fix is the late model pilot bearing.

I will add that I have taken apart more than one numbers matching automatic car that did have pilot bushings installed.

They put them in stick cars all the time and occasionally in auto cars by mistake.

That may be where you are experiencing the idea that automatic cars get them too.

Interestingly enough, when I converted my Diplomat to stick it had no problem with me putting in the old school pilot bushing. They quit putting sticks in M bodies in 81 and then I think it was only /6 cars, last year for the slant as well.

So the answer is, you won't know till you take it apart and see.