Hole Spacing - Planning Plumbing

[GoldStripe]

Here's my planned setup:
(2) 1.5" drains in Calfo overflow.
(2) 1.5" closed loop intakes about halfway down.
(2) 1" closed loop outputs all the way down.

I've got the drains to the sump drilled and I'm try to figure out spacing for the next set of holes (cl intake) I'm thinking about 11" on center inside the drain holes. Of course they will be down towards the middle of the tank vertically speaking. This would put the CL intakes at 15" on center from each edge of the tank.

In between these 1.5" holes will be two 1" CL outputs. These will be down as low as I can go, probably 2.5" off the bottom of the tank. I'm just trying to plan out ahead of time because I know how fun it's going to be working with 1.5 PVC under that stand and also working with those huge Hayward true union ball valves.

Any thoughts are much appreciated. I'm ready to start drilling again!! :)

[flowerseller]

Have you ever used the blue "Rain-R-shine" pvc cement?
It's the same glue as for flexible PVC like spa hoses.
I like it much better for ALL pvc than the traditional clear Oatey cement. It allows you to see your joint much better due to the color.
The blue cement is also made by Oatey