Honestly, and openly, I use the 3" Carrot as my Shrimp, just rig it tail-horizontal. My plastic color and jighead color are both Shrimp, so I'm good to go. The profile is close enough.
Corp, You can use the 3" Carrot and add a flared Shrimp tail, You'd have a well-enough Shrimp.
Throw in a tail mold, wallah. It really is that simple if You want to keep it simple...BUT if You want to go iToldYaSo, then the sky's the limit.