Okay, according to my shop manual, the piston pin bore internal diameter should be no more than 16.08mm (0.633 inches), and the piston pin itself should have an outer diameter of no less than 15.98mm (0.629 inches). Piston pin to piston clearance should be no more than 0.06mm (0.002 inches).

The Connecting Rod's small end internal diameter has a service limit of 16.08mm (0.633 inches). That sounds familiar, eh? And the connecting rod to piston pin clearance has a service limit of 0.06mm (0.002 inches).

Now, it doesn't have piston pin length, but service limit of the piston outer diameter, taken at a 90-degree angle to the piston pin hole is 59.86mm (2.357 inches), so it's safe to say that the piston pin shouldn't be much longer than 2.357 inches.

Okay, here we go. more information in the book that I hadn't spotted.

Piston pin bore is usually between 16.017-16.028 (0.6306-0.6310 inches).
Piston pin OD is usually between 15.994-16mm (0.6297-0.6299 inches).

Normal range of piston to piston pin clearance is 16.016-16.034mm (0.6305-0.6313 inches). connecting rod small end internal diameter is 16.016 to 16.034mm (0.6305-0.6313 inches). And piston pin to connecting rod clearance is 0.016 to 0.040mm (0.0006-0.0016 inches). Phew!

Normal range of piston outer diameter is 59.970-59.990mm (2.3610-2.3618 inches), and normal range of piston to cylinder clearance is 0.010-0.045mm (0.0004-0.0018 inches).

This manual is pretty entertaining. The cylinder/crankcase/transmission chapter opening illustration shows the engine upside down, which had me confused for a few seconds. :)