I didn't have to notch my k member with the schumacher mounts. If I was you, I'd find yourself a 400 block and build a 451 using your 440 crank. The lower deck height will make changing plugs much easier. I wish I had done that. Pro parts headers fit great. I just had to do a little hammering around the mini starter and the idler arm. I also had to bang on the pass side valve cover to clear the blower motor.
I built my own z bar but I think I might switch to one of those kits from brewers because I'm not getting as much throw as i need.