You need to select the camera carefully (or have it converted). All modern stuff have strong "heat mirrors" ahead of the sensors, and you will be facing exposure times in full sunlight verging in MINUTES!
Go here to see an early version on the rig. Dual Minolta Dimage 7 cams (IR sensitive without mods) and ca common release. I have upgraded to a cheap metal bar that permits a wide range of interaxials.