First 351 Windsor or 351 Cleveland? Different Blocks and parts. Which could start another whole debate. You will have more power with either (Properly built) They are bigger and heavier then a 289 or 302. More parts available for the windsor (which is in the same family of engines as the 302).
swapping a 351w or 351c in place of a 289/302, pros larger displacement capacity(up to 427ci with the stock block) more torque capacity more hp capacity cons tighter clearances(requires swap headers) more weight(unless you use aluminum heads to bring the weight down) high fuel consumption(if you care about that in this application)
