Spacers are a good idea but require a nut capable of locking onto the die. My Lee dies only come with rubber O-rings which is fine if you like changing and adjusting dies. That's why I got a turret, so even with my dies when I get all this stuff figured out I can hopefully just set it and forget it. Do you buy these spacers or have a punch and make them yourself? Regarding your crimp, how would a roll crimp change your particular round's function (accuracy, cleanliness, ...)?