one good way to tell if you will ever come close to getting a good seal is to remove the frame from the crank and the hinges and get a couple helping hands to push it against the cab to see where the gaps are. If you have a replacement windshield this will show you if you need to bend the windshield (v bars) in or out to get a closer fit. Once you get it as close as you can re-install it. The hinges are slightly adjustable both where they attach to the windshield as well as where they attach to the cab header panel so you have to play around (using those extra hands).
Once you have everything re-installed and tighted; go to the local wal-mart and buy some rain-ex and an extra towel. The rain-ex to keep the windshield clear and the towel to dry off your dash and floor.
As for the location of the drain tubes: Kip is right on.
p.s. having a good cranks is key. This is one of the few things I have yet to do - rebuild the windshield crank to get it to pull tight.
