Details to convert pressed piston pin to full-floating?

The .040 over pistons have four valve reliefs and tru arcs.

One connecting rod ends in "496" and the other seven end in "645".

Oddly enough, on Ebay right now are a complete set of NOS 340 connecting rods:

1971-73 Connecting Rods X8 340 CID MOPAR NOS Part Number # 2899495 In Orig Boxes | eBay