contrary to what everyone else has said, it CAN be done.
all you will have to do is lower the compresion ratio, fit a 5th injector to spray a mist of fuel into the intake manifold, reset your carb, run a oil feed to the turbo, rework the plumbing of the exhaust system to accept the turbo, fit an intercooler, adjust the timing, ensure you are runnign the correct boost, replace your block bolts with stronger ones, fit a high lift cam, stronger valve springs,.... on 2nd though don't bother doing it:P