Ghetto Jet· current hot rod: CTS-V
Taking the heads off is an easy job, I wouldn't turn it into a rebuild that isn't needed. You could probably grab a better set of heads off ebay/craigslist or a ford forum for cheap.
I've seen engines making real horsepower run over 300,000 miles without issue. This 351 will probably be making a whopping 260 horsepower, the extra stress will be negligible. Although I would change the timing chain if its original.if you use these your bottom end will go boom. an old motor does not need hp thrown at it. just get the old bolts out that broke off . and rebolt them on. you say you do not want to throw money out the window. put on new heads and you will spend a lot more down the road as most of the parts will not be useable on the rebuild. like the block with a big old hole in the side of it:nono: