Adapted this Plier rack by prozach - https://www.thingiverse.com/thing:3776187 to fit the IKEA Skadis pegboard system.

Supports will be required for the upper pegs, you should be able to set enforcers such that the supports do not touch the bottom pegs and are very easy to remove (see screenshot)

This should fit tightly into the rack without any post processing as long as you are cautious while installing it - ensure it is fully slid down on the top pegs before pushing the bottom pegs in. My initial print fit and i've increased tolerances slightly from that but worst case you might need to sand down the bottom pegs a little bit.