not at all, but prepare to spend up to 10 grand. I've seen the engines go for as high as $7000 and the tranny's as high as $3000.I was really hoping on using a duramax though. Are they bad motors?
The problem you are going to have is getting the Duramax electronics and the allison and everything to work, probably going to be a huge pain in the ass. Your going to need a lot of stuff to make it work. Thats why a mechanical 12 valve cummins is so much easier, plus the fact that they are bulletproof once built :imo they will last for a long long time. If money is no object why not buy a truck with a duramax in it and go from there? Project truck?
edit: Banks blows donkey hole. Seriously, if you want to get into tuning your Duramax if you decide on that, then look into EFIlive. Also head over to Dieselplace.com People seem to be a little older and more knowledgeable over there. I bet they would like your idea of the swap.