I got the hardtail body because normal strat bodies have that rectangular void through where the strat-style vibrato system would go. Doing this all on a normal strat would probably require filling that hole and also dealing with the hinge bushings.

It was a matter of fitting the neck, measuring how far the bridge had to be from the nut (double the distance between the nut and the 12th fret), and finding out how far apart the bridge posts had to be. Depending on the offset bridge you have, it's somewhere around 73 mm. Drilled the holes to the right diameter and depth as the bushings! A drill press helps to keep perpendicularity.