I agree 100%. It took me a solid 36 hours of non-stop work between when I pulled the 300TD into the shop and driving the 240D out the door under it's own power. Thats having all the hard bits already done (driveshaft shortened, shift rods shortened, etc), the engine and tranny already out of the 240D and some decent skills as a professional mechanic.

There is no way a weekend mechanic could put in a non-stock engine over the weekend unless they have some great hidden talent or multiple helpers pulling their weight.