Submarine Counter Highlighter

Sometimes I find it hard to find a submarine counter in the board game Wolfpack from GMT with older eyes. The counters blend in amazingly well with the game board. This is just a nothing special simple little submarine counter holder with a direction indicator to help you locate the submarine counters a little better.

Update (Thanks to Mark W. BGG user for the idea): Added U-Boat board labels in case you decide to print the counters in different colors that those defined in the game.
Game U-Boat colors are:
W - Yellow / Gold
X - Brown / Bronze
Y - Green
Z - Blue

Printing Note: I would probably print the the board marker separately from the counter holder just to minimize any stability issues the printer may have when jumping between the pieces. The markers are printed on end. Additionally, make sure you have smooth corners on the inside of the board marker (use an emery board, etc.) where the marker met the printer bed so you don't scratch the U-Boat board. The markers should fit loosely on the boards.
Sorry for the lack of W, X, Y, and Z labels visible in the marker label pics -- they are there. No idea how to rotate those pics to show them.