Butter up your local dealer,and see if you can buy a warrentied 6.4 truck block when they get one. The local dealers up here only get $900 Canadian for the core 6.4's when they replace one. Kurtis/Charonblk beat me to the last one our local dealer had,but they do show up occasionally,and most dealers it seems would rather sell the core,then have to package it up and send it back to Ma Mopar.The 6.4 truck block is basically the same block as the 6.2 Hellcat block with the good big gas heads.They make a great foundation for a 426 build.