Re: 1987 Harris 280 heritage
I might suggest that you angle the rod holder slightly down at the rod tip end..
1) it would allow any water that's on the rods/line or gets into the open ends, to drain out.
2) tilted down, the rods would be more likely to stay put when trailering, backing down the ramp, or bouncing thru waves & wakes, unless there's a retention strap that's not yet installed.
3) keeps them in the tube when you drop the throttle and the boat JUMPS on plane w/ a high power hole shot. Those ^^^ retention straps may help here too.
Ok, perhaps #3 is somewhat unlikely

straps would be a good idea anyway to decrease rattling fishing gear
#1 would allow you to easily flush/rinse the tubes if needed as well.