Does anyone know if a 300 6cyl with carb will go in this truck

 

If you are a good fabricator you can get any engine in that truck IMO. A buddy of mine has transplanted 302 fords into late 80's ranger 4x4

 

I had an '84 Ranger once that I had a 327 Chevy small block fitted into it. It fit with a bit of hammering on the firewall but before I sized it up for that one I checked out putting in a small in-line six I had. Even a small six is still longer than an eight and just too long unless you want to make it fit way under the dash. As I remember the six did leave a whole lot more side room where if your truck isnt a low rider you might be able to cradle it way low in the frame.

Like the other guy said, if you really want it in there you can make 'er fit.