to use the 6.4 crank and the stock 6.4 rods you would need a custom piston with a pin height of 1.187(take into account the clearance taken up by oil film when the engine is running) no one makes an off the shelf piston with that height.

Edit ....Icon has a piston IC649C-0015(3.3 Dish)IC650C-0015(13.7 dome)IC648C-0015(17cc dish) which is a pin height of 1.165 , so you are looking at -.025 below deck with a 9.25 block height..issue is the 6.2 stock rods are .945(or.984, I'm not sure) pin dia and these icon pistons are a .927 pin Dia




Now here's a combo that I've seen my builder do a few times.
Eagle Block
6.4 Crank, Rod Journals turned down to 2.10
Compstar rods CSA6300DS2A2AH. 6.30 C to C with .927 pin.
Icon pistons IC653C-0015 , 3.9185 bore ,8.7 cc dome, 1.09 Pin height.
Cometic Head Gaskets C5467-060
this is a true 0 deck height with a 9.25 blue print block, once clearance slack is taken up by oil film in a running engine the pistons will be about .0025-.003 above the deck.
Makes 12.0 to 1 with Eagle heads
358.9ci
Stock Eagle heads, SRT392 Non MDS Edelbrock intake. 90mm TB
Made 498 Hp @6100 and 510tq @ 4300. with F.A.S.T ignition system. using a 6.1 32 tooth tone wheel.