A clean '66 is worth more in unmodified condition.
Certainly it can be done, but you would basically need everything.
906 Pistons 10,3:1
Titanium Rods
46 Webers
906 Cams
Modify heads for twin-plugs
Twin-plug distributor
Increase valve sizes from 39/35 to 46/40 and port from 32/32 to 38mm intake and exhaust
226MM fan with fiberglass shroud
Case windage modifications: knife-edge, boattail, moon cylinders
85mm Aluminum Cylinders (906 style)
Megaphone exhaust
And then you would want to make all the modern updates to the case: oil bypass, squirters, etc.
The car itself would need dual front coolers like the R to control all that heat.
By the time you were finished I would not expect much change from a $40,000 bill and the engine would have a 40-hour life between maintenance rebuilds.
But the sound. . . .that beautiful sound. . . it's only money, right?
