It's going to be filled up as a turtle tank so lots of circulation is what we're going for. (Water will be to the top with above tank basking platform)
i built a 42" return for my wifes 75gal goldfish tank on with 1 hole every 1" the filter is a Eheim 2260.the current is barely noticeable but buttom stays mostly clean.so i think it will work fine on your tank.
I took one end off and it still came out ALL the holes just dont want to cut down the flow to much might end up shortening and drilling holes bigger too...