How Hard To Rebuild Engine?

[OldAudiA4]

So as the title says, I'm wondering how hard it is to rebuild an engine? I'm not a mechanic. I have changed engines in cars before, but never rebuilt. Does anyone recommend any good guides? I was actually at looking at rebuilding a Subaru Boxer engine. I'd imagine the principles would be the same (except the fact that it's a boxer engine).

[QuattroBucc]

I wouldn't say its hard at all if you're mechanically inclined and have the proper tools. Just go through the proper steps to do it right. New bearings/rings/lifters and valve stem seals are all pretty easy jobs if you have the entire engine apart. You just have to make sure you torque everything correctly and put it back together correctly, for me the toughest thing since my motor is AEB was replacing the bearrings for the secondary shaft that goes through the block to run the oil pump since they're fully circular bearings you have to line up the oil holes with and they're a bitch to install without damaging