OK - and me as a SBF 'enthusiast - that 302 as it stands is kind of a weakling. Many of them crack from the cam bore to the front main. That means the first thing to do is tear it down, hot tank and thoroughly clean it then have it mag particle checked at a minimum Then if you really want to stroke to 331/347, then you need to get even more involved with physical and dimensional checks. I would not do .040 as my initial bore on a thin wall casting, but would limit it to .030. As far as a future blower/turbo, quite frankly, that engine is probably a poor candidate. Ford Racing offer excellent alternatives for probably less then what you will be paying to get your worn out OEM engine brought back to new specs. Not what you want to hear, but a reality