Drivability problem.. please help asap

I'm helping my friend with his dodge ram pick up today. I think he said its a 1985 or so. What he told me was, when he's driving uphill, his truck studders and chokes, and will sometimes die. I'm assuming its either because of the carb idle/mixture settings or a vacuum leak?

if this problem sounds familiar to anyone, please lemme know your thoughts.

Thanks.
-Logan