Here's a multi-color core-shot with all of the baits still hanging on the sprue.

The pink bait at top right was done using the conventional do-it black colorant. Applied full strength it still doesn't have enough umph to get this job done nicely. A drop of black was placed at the front and the back of the pink belly pour yet all that shows is a slight tinge at the end of the belly color and a slight wash thru the tail. All of the other core colors are done using the X2 product. I did this to show the need to use a strong colorant and the X2 fits the bill.
I'll decide on eyes once they are cut from the runner and I can look closer at them.