Depending on application, extra thread adapters will be need to be inserted prior to the correct adapter to act as a spacer for the FRS/BRZ/GT86 6 speed manual . This is to gain enough clearance for reverse lockouts.

You can purchase that adapter here 

http://www.86speed.com/products/blox-racing-shift-knob-reverse-lockout-adapter.html

• Limited edition collaborative design by Ryan Tuerck and Mishimoto
• Perfect complement to every interior, from missile car cockpits to daily drivers
• Handpainted design influenced by the iconic Ryan Tuerck style
• Billet aluminum design weighs 5.46 oz
• Ergonomic shape allows for smooth shifting and comfortable hand position
• Purchase includes three aluminum alloy insert sizes to fit various applications
• Mishimoto Lifetime Warranty