three gpu watercooling setup

[ComputerCurious]

So I am going to cool three gtx titans and need help figuring out the setup with the fittings. Right now I'm thinking this: http://www.hardwarecanucks.com/forum/attachments/water-cooling/2016d1209678222-series-vs-parallel-tri-fire-watercooling-tri-xfireseries.jpg the inlet on the top card, the sli fitting to the second card, from the second card to the third card with the other sli fitting, then on the third card the outlet. I'm going to do it in a series. Also my concern is once i put the sli connector in the cards how am i going to close the hole to get the water to flow into the other connector?

 

[inzone]

Each water block comes with two plugs that go into the unused holes, so on each card you have four holes two of which have an SLI fitting in and two which will have plugs in closing the holes and forcing the liquid through the fittings.
This is what the plug looks like;

http://www.performance-pcs.com/catalog/index.php?main_page=product_info&cPath=59_346_393_612&products_id=28733

What is your reason for running three GTX Titans ?