piston to wall measurement

Like Pishta and the others said..
The bore size is normally the "oversize"... so a 360 nored .030 over would have a bore finished to 4.030". The clearance is built into the piston - so measuring the piston (assuming it's a KB hyper) should give you 4.028 to 4.0275.
Pressed pin or floating pin is a function of the rod. 360s are factory pressed pin so the rod pin end is heated, and the pin is slid through the piston and heated rod, and when the rod cools (seconds if that) the rod grabs the pin. So no pin locks are used or needed. Full floating pins mean the rod's small end has the larger diameter and normally a bronze bushing and the pin will slide in and out of the rod. That's why you need the pin locks to retain the pin and keep it out of the cylinder wall.
Normally the floating pin is best in terms of putting up with abuse. The pressed pins can "walk" out and into the cylinder wall under heavy abuse.