i've not done a whole lot of head work so i don't have alot of experience with valves and such, however, everything else was rather easy. Craftsman makes swivle 10/12/14mm sockets and they came in handy alot. things like taking the intake manifold off. it was a 5 minute job with that swivel 12.
other than that, find a good shop manual. (well worth the investment) and pay attention to details. The 240 is pretty easy to rebuild, its not like some other imports where you need a 10, 13, 15, and a 16 mm all in 6 inches.
good luck