Carburetor Help??!?!?!?!?!

hey yall,
got a carb question. My 1960 valiant has the 170 slant 6 engine with the carter single barrel carb.

i've read that changing to a 2 barrel would greatly improve performance. my car is slow, 50 to 55mph puts me running from 2500-2800 rpms. i try to stay under 3000rpms to be safe since im not sure what is "safe".

question is, my carb works fine, BUT, on hills or the need to push around a tractor in the road lol, i have the pedal to the floor to get up the hill, would a 2 barrel carb help with this, and how do i know what carbs will fit???? just need a little more punch when i hit the gas pedal.
also from what i been seeing during my searching, there is regular carbs and also "super six" carbs, is there a difference in these?? im just not sure what will and wont work.

any suggestions???