My first impression is that illustration is for a much newer version of a 318/360 engine ... 1980s or later.
"Throttle positioner" implies drive-by-wire versus mechanical/cable throttle linkage.
It also looks like a TBI/EFI air induction rather than a carburetor.
Given that impression, it's (very) roughly what you're dealing with and a starting point.
IIRC, you should have a plate, roughly 1/2 inch (12.7 mm) thick, between the carburetor and intake manifold. (Looks somewhat like a carburetor riser.) Usually, during your engine's era, the EGR valve is attached to that plate.
(This is based on decades-old memory so don't take that as gospel ... plus I've worked on a lot of different engines and sometimes have trouble recalling details on a particular engine.)
There's been a lot of variations in EGR system configurations over the decades. (Basics are similar but details vary greatly.)
So, you want to look for information specific to the EGR system in a '79 Dodge 360 engine. (Note that the illustration shows a difference between 318 and 360 engine in terms of throttle positioner.)
Will do some digging and research.
