If the seats you have are the # 47 (you mentioned flat bottom)These recommendations are on Kirkeys site.
http://www.kirkeyracing.com/related/...on%20Guide.pdf If you have the 45's there are instructions for those seats on their site as well.
I have the # 63 seats but they're somewhat similar in that they're intended to be mounted solidly to the cage. You can see the full process of how I positioned the seats and how the seat mounts become part of the cage structure here.
http://www.pro-touring.com/forum/showthread.php?t=48151