don't know if its easier but just from having had the top end rebuilt on my 560SL which started as a timing chain replacement, the mechanic who worked on it did not pull the engine from the bay....however, I caught it before the timing chain broke and so no damage to the valves caused by chain breakage.
in the end, the valves were replaced anyways due to other issues.
basically he was able to replace most of the moving parts on the top end of the engine, the chains, the gears associated with the chains, oil pump, and assorted hoses and such without removing the bottom half of the engine.
Network Integration Engineer
MCSE, CLP, CCNA