new here and a lot of questions?

Hey everyone, looking forward to getting some help from what seems to be the most informed people on the net hence why I chose to join this forum.

I have a 1964 Plymoth Barracuda, 273 with a 904 push button. I wanted to swap out to a 4bbl intake but now seeing thats gonna be a challenge. Any info there would help. How to redo an aftermarket to fit ?

Also my brother offered me up a brand new cam, its a Crane brand but stock spec for a 340. What all would i have to change in order to run something like that ? Would I have to go from solid lifters to a hydraulic ? Would I have to change pushrods from that early 273 ?
Thanks again