Sump plumbing planning

I can't drill the tank. Just to get that out of the way. I'm looking for a hob overflow for a 120 to go to the 39" trigger sump. It has 2 or 3 (interchangeable) 1" drains built in and I'd like to keep these. I also would like it to be able to handle more then 10x turnover, simply because I want to have the choice and see what works best for me, high flow or low flow. I was thinking of the eshopps pf-1800 but don't know how to swap the dual 1.5 inch for two or three 1 inch without plenty of fun plumbing. The marine depot of- 1800 only has one 1.5 inch so it might work better?.

I'd like some opinions and just some help, because all the research is getting overwhelming. Thanks