64 with Aluminum but that is huge money. Might have to acid dip a few panels to take some weight off. NSS with a 605 Hemi, some were I live are making a lot of HP over 1300 but you start to live on the edge. Would rather back the motor off and go 899 without hurting things. Only other way I see it to change to a 67 8 9 A Body. there is your weight loss and 67=8=9 all have Big Blocks and 68s Hemis. One problem that was found is the front end on a 68 Cuda with a 605 making a lot of HP the MPH at the top end makes the front end of the car feel very lite,