if your gonna take the engine apart, it's jus as easy to take it out than to gaze up at it on a ramp and fuck your neck, you wont need to take the head off if you want to do jus the bottom end, but i'd want it off to inspect and renew the gasket if I was sorting the bottom end!

look out for a good 2nd hand engine if you cant get yours re-built for a reasonable price, maybe a freshly built one from a reputable place, dont wanna buy a so called GOOD one if its crap!