G - Very good athletic ability and college production.
Doesn’t meet minimum height requirements, but meets weight and speed requirements.
Examples – Sam Mills & Antoine Winfield

INJ - Player is recovering from an injury and will need to get healthy before he can play up to his physical ability. (This is for the broken ankle he suffered last year)

6.3 - Very good starting player (2nd Round talent)

GM Junior's rating system is described here....

http://www.sportsline.com/nfl/story/9377197

Clemens' profile

http://www.sportsline.com/nfl/players/draft/408416