The coolant capacity is in your owners manual. Whatever it is just cut it in half and that's how much of each.
I think I bought 2 gal of antifreeze and 2gal of water for the fill and another 4gal of water for the flush.
Have you considered the zerex antifreeze. Its cheaper, provides the same protection and is available at napa
2007.5 Black Ram 2500 MC SLT 6.7, 2wd, 68rfe, 3.73 diff, Edge CTS, SmartyJr street tuning
Stock except for PML trans pan and 2 add on fuel filters (delete parts are in garage)
Darn if the egr plug didn't fall off again! (And again and again)