I would question why there is a leak at that particular location and not other places? Just curious.
In looking at the Chrysler parts book for that model year, I see in the engine "exploded view" for the "Single Rocker Engine", that the particular gasket looks to be coated with a thin layer of a metallic substance. Not unusual, but usually seen on the exhaust side of things. Not unusual for back then, from what I've seen over the years.
As to using sealer there, certainly do so if needed.
My method for ALL gaskets has been to put a thin skin coat of black high-heat sealer on ALL gaskets, using a Mr. Gasket gasket scraper to ensure sealer gets into the nooks, crannies, and made-in beads of the gasket. Then continue to put the skin coat on ALL surfaces . . . top, bottom, inside, and outside. Leaving the texture of my fingerprints as I smooth the sealer on. NO need to "build up" the thickness of the sealer, but just to get a thin coat on everything. THEN, let it cure for 24 hours. THEN install it to factory torque specs. Use a new gasket, too.
One of the benefits is that should the gasket ever need to be replaced, it will come off the castings with ease with less clean-up time involved. With the other benefit is that no fluid will wick through rubberized-cork or pure cork gaskets (as the lighter parts of motor oil will do).
I have used this method on every intake manifold gasket I have replaced, plus other engine gaskets. Even the thick OEM-style carburetor base gaskets. Since the earlier 1980s. No problems. Just something I started to do to end valve cover gasket seeps, then went from there.
For good measure, after you put the new gasket on, with my tweaks, after the engine has had a few hot-cold cycles, DO go back and re-check the bolt torques, in sequence, just to ensure everything is where it needs to be.
Hope this might work for you, too.
CBODY67
