Got an 83 Ram Charger with a 440 today!

I fondly recall a top-o-the-line '86 RC that I bought in '88. Yeah, it was hard on fuel with an enemic 360 and the Rotten-chester carb...

Here is a trick that 'usually' works for broken bolts/studs, but for an intake manifold you need to take the manifold off unless you can be damn sure there is no fuel vapor in the air...
Since you are dealing with a 'hot' area, run the engine up to operating temp, then smear some beeswax around the broken bolt in hopes of getting some down into the threads.
Next, place a thick fender washer on the broken stud.
Now the fun part (remember the fuel vapor issue...), weld the stud to the washer. Then, place a nut on the washer and weld it down.
Before it cools completely start rocking the nut back and forth with an end wrench, and if you can, force more beeswax in there.

The option to this is to drill out the stud and if necessary tap for the next larger thread size.
You could also just buy a manifold off of ebay...plenty of them available, w/ and w/o egr, std and spread bore, alum and iron.

BTW, that engine looks to be exceptionally under the valve cover. Nice score!