how hard would it be and around how much would it cost to swap my 92' FlareSide's 302 to a 350?

 

Er- do you mean 351? 350 is a chevy engine. converting between makes would be a b**ch. a 351 is built to bolt up to the same transmissions, so a 92' 351 should be a reasonable swap. make sure that you have all the wireing from the 351. there might be changes in some of it. wire it up so that it is the same as it was where you found it.