It does not "Drop in"
Ading the crank, without adding the rest of the combination is the biggest mistake we see.
One must approach the assembly of an engine of this caliber with a "Performance mindset". This means that when ONE part is added that adds performance, EVERY part that relates to that must be altered. In this situation you must attain the proper rod ratio, and proper compression height on the pistons, as well as choosing a cam that gives you the correct characteristics for you head flow, as well as the fact that it must "physically fit" inside the case, without colliding with the cam..
Do your homework before you buy the first part. Parts are available that will drop right in- but not off the shelf, unless its a shelf of mine.
BTW, we use standard 66mm stroke cranks to make our 78.4 with a Type I rod journal. The66 stroke crank had a 2.165 rod journal just like a TI, its just wider on the big end....