125-200cc clutch basket rivets..

replacing my basket and i ordered new rivets.... how do i flatten the end? it is flat like the head of a nail and has a blunt end on it.. do i install the flat round part on the gear part? or inside the basket? any suggestion for tools or a step by step is welcomed..

also does anyone think id be able to tap the basket and use screws... its a oem basket. im assuming its alumnium. any info would be great would like to have it together this weekend. thank you