Going second hand can be a risky business on certain items, I would get the main parts tested like the turbo / injectors etc if i bought them 2nd hand just to be on the safe side. I had a slightly faulty injector on my first build and I melted a piston :S
i'm hoping to have a decent turbo set up on my k11. it's going to take a while to do though cos i've got to save for the parts needed (i've got two kids and they can suck your bank account dry. lol ).
i have purchased a cg13 auto engine (from raceworx) already stipped down it's a stronger block than a manual cg13 as it has strengthening ontop of the wet lined cylinder walls.
here's a couple of pics. !st pic is manual block, 2nd pic is auto