Keep in mind that 05-07 models are different than 2008. In 2008, they moved the auxiliary trans cooler from the right to the left side. IIRC, on the 08 model, the right side cooler hose goes from the right cooler trans line up to the auxiliary cooler. The other hose from the auxiliary cooler runs to a barbed fitting at the left side of the radiator, which connects it to a hose that goes to the left fitting on the radiator. The right side fitting has a hose that connects it to the left trans cooler line. So, the flow is from the trans, to the auxiliary cooler to the radiator and back to the trans.
All you need to do, IIRC, is remove the cooler hose between the barbed fitting and left radiator cooler fitting and the hose between the right radiator fitting and the metal trans line. Cap off the two radiator cooler fittings (clean out the cooler first, if you want). Run a new piece of 3/8" ID trans cooler hose between barbed fitting and the left trans cooler line. You should lose any noticeable amount of fluid, but check the ATF level when done just to be sure.
As far as parts, you can get them at the local auto parts store. I got my trans cooler hose off of Ebay. I purchased 6 ft. of it because I have two that I'll have to do soon. You'll probably need about 2 ft. of cooler hose, but I'd rather have a little extra. If you want the Nissan constant tension clamps, you can get them online or from Ebay or any Nissan dealer. If you have a nearby Nissan dealer, it may be cheaper from them due to shipping costs.