i see, well get everything rigged up and if temps are unsatisfactory, you know what you need to do :P just make sure you have the 80mm of clearance the rad needs between the mounts and the top of the vrm heatsink! also if you mounting the fans on the inside of the case this will add 25mm, unless you get some low profile ones which are usually 15mm.
as regards sli, have a look at some of the benchmarks linus put up when testing the titan, it is certainly the best single gpu card. if you can justify the expense, go for it, you certainly won't be disappointed. are you planning on doing surround gaming? if not the only game you would need a card like titan for is crysis 3, but thats for now. with the increased memory of the next gen consoles, high memory cards could be a necessity for modern gaming in a year or so :)