Do I understand you correctly in that the light itself fits, but the power cord sticks out the side & that is the problem?
Depending on your hood/light I can think of some DIY solutions.
Some lights comes with knockout holes to allow you to move the power cord. If you have some house wiring experience, it is not difficult to move the power cord to a different location. <You have to open the light, disconnect the power cord from the ballast/switch, move it to the knock out hole of your choice (you will need a wiring clamp for the knockout), and reconnect the wires exactly as it was before.>
Alternatively, you may have to drill/notch the canopy to fit the wire. <This might look ugly, depending on what you have to do ....>
80 gal FW with 30 gal DIY wet/dry/sump.
9 fancy golds, 1 hillstream loaches, 1 rubber-lip pleco (C. thomasi), 3 SAEs, small school of white cloud minnows, planted.