The B&M Kit I got does more than that. It comes with drill bits to to drill the separtor,springs and some kind of spacers. Maybe the one your talking about is the shift improver kit. I think mine is called Transpak.

 

The stock transmission survived 4-1/4mi passes the built transmission lasted about the same.It had servos,hardened shell,torque drive,hardened shafts,performance clutches and more.Now it's being replaced with a built 4L80E.I guess I'm a little harder on transmissions than the average driver.

 

nomore than me i went through 4 transmission rebuilds in one month...lol
the tansgo goes way more in depth on correcting a few things that gm didnt up grade on.
the B&M is just a typical shift kit.
granted the B&M made it shift harder the transgo can be adjusted to your likeing of how hard you want it too shift.