An update. I did order the 36" Ray II (Dual 7000K) from Amazon. It arrived today. To answer my own question, the light is just about 35 1/2" not including the switch/electric wire (which adds about another 1/4" or so). It had no problem fitting within the 36 1/4" hood.
Now the bad part. Amazon shipped it without double boxing it. It arrived in the original box (all banged up BTW). The box was partially torn and the best part is that the "feet" did NOT come inside the box. It probably fell out of the torn box. Needless to say, I am returning the unit to Amazon.
All the physical measurement aside, I have to comment a bit on the "brightness" of the LED light. I am trying to replace my power hungry AH Supply 2x 96W (36") compact kit. The current bulbs are about 1 1/2 years old, so they are not the brightest. I have no illusion that a 30W LED set will replace 2x96W PC. I was ready to buy another Ray II once I know it fits. However, I am a bit disappointed on the output of the Ray II. I don't have a meter, so I can't comment on the exact number. However, a simple "naked eyes" side-by-side comparison says 36" Ray II output significantly less light than a 1 1/2 years old 36" 96W compact.
Perhaps I got a bad unit or my expectation of LED is unrealistic. I guess I may have to go the DIY route.