Are you using an LT1/LT4 6.2L Corvette swap in your project? Do you see that you may have a problem with clearance between the lower radiator hose and your radiator? Then you NEED this RM Motorwerks LT Thermostat Housing!
Not only does it convert the lower pipe from forward facing to down-facing, but it also allows you to 'clock' the upper hose to fit whatever hose inlet direction that you need! Simply undo the the 3 bolts, and you can rotate the housing!
This conversion allows you to also use the LS-style thermostats for a great selection of temperature choices!
*** This does require careful modification of the factory water pump housing to fit. The lower radiator hose tube needs to be cut shorter, and the top edges of it carefully smoothed so that it does not have a sharp edge anymore. This cut should be done just below the 'ridge' on the factory neck. You should remove the factory water pump housing from the engine for this modification so that metal shavings don't enter the system.