1969 Dart Swinger

Well I went to look at my next project today. 69 Swinger 340 4spd car. Current owner is the second owner (since January this year). Car is B5 blue, White Vinyl top, looks like maybe a stripe delete car. It has the fender tag & build sheet. I remember this car when I was growing up (born in 64). The car has everything that was originally on the car minus the 340. I get a 73 340 but it has two cylinders that have hairline cracks in them that have been sleeved and guaranteed by the machine shop for 3 years 30K miles. What are your thoughts on rebuilding the sleeved 340? I will be picking up the car next Saturday and bringing it home. More pics then. The 63 belongs to the buddy of mine that I am buying the Dart from.