The Mercedes engines are about as easy to pull as any engine in the world. You don't even have to remove the hood! The car should be up on stands in the yard so it's pretty easy to pull the bottom stuff - though I agree that it's a ton easier at home - I have a hoist. I did mine in 3 hours at home and I'd guess that would take 4-6 hours in the yard.

While I'd agree that pulling an engine at a salvage yard is somewhat of a chance I still think it's your best bet given the tough nature of these engines. Just do the most thorough check you can before you pull it.

Dan