There is not easy answer and I for one wish there were. The major problem is balancing the mass of refrigerant required to cool 150W+++ and get an evaporator that will fit on the die. I think I have discovered a way after months of research but will hold back until I can verfy that it works in practice. The most common problem is that those that have tried it either end up with good cold temps on trial but poor results because they don't have the mass required or the evaporator is not producing low temps but is cooling the proc.
Here are a couple of links to sites where they have done it
1st and
2nd .