| I have modified most of my lamp assemblies and even built (or paid someone to build for me) the lamp assembly unit. If you are handy with electrical work, then I don't see why not. Get as efficient electronic ballast you can afford, place it remotely, and wire following its diagram. Rule of thumb is to use same wattage lamps. You can combine the color temperature as you wish.
In my 20gal tall custom built Nano Reef tank I have a wooden frame holding 10 lamps. I use two electronic ballast designed to handle up to three 32W lamps for three T8 20W lamps (10,000K, 18,000K, actinic) each, and one electronic ballast designed to handle four 54W T5HO for four T5HO 24W (all actinic).
The easiest way I've found is to work with the plastic lamp assembly, dismantle the hole thing, paint the interior walls with as bright white spray paint I can find and place two or three T8 lamps, using a remote electronic ballast to run them. I use a soldering iron (not a socket) to wire them, place a rubber cap around, and if needed be, use tie wraps to align the lamps as desired.
Using Normal Output T8 aquarium lamps, I have upgraded a 36" lamp assembly from 20W to 90W. In a 30" lamp assembly from 20W to 75W. In a 24" lamp assembly from 18W to 40W.
For a bit more of money you can purchase retrofit kits of high quality and upgrade your lamp assembly with Power Compacts.
Pepetj
Santo Domingo | 
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