on a 69runner with non air grabber hood with the std grilled inserts can I unbolt them and put the screened air grabber units in??

Why not? You need the whole under hood arrangement to make it work though...

yes I know but at least it will release some of the heat from under the hood.....and I like the look of em

That's the difference in the factory parts, screens vs plates

There are a lot of little parts to do the changeover. The little "L" brackets are a different length that hold the long bars under the screen. Some of the original ones sagged in spots and rattled on bumpy roads because of the wrong sizes. You may be able to rebend or modify them to work and seat on the bar. The screen and bar is thicker than the aluminum insert but I have seen a few that have the brackets just holding the screens with the bar flopping around.

FYI some cars came with double stacked screens in one louver because the long bars weren't there. A couple of the cars I owned were that way, and all the cars I found like that were doubled on the same side. Don't remember which side, but we could come out of a wrecking yard with three screens off of a single car. This was a RoadRunner quirk from the day.

looks like they sell screen kits....pretty sure comes with the L brackets and specific long bars....I will makes some ph calls tm to confirm....thx guys

Do it! Way cooler than the ribbed block offs and most modern hood scoops are called air extractors anyway. A little water won't hurt anything if you get caught driving in the rain.