Hi. Here is a good way of making your own Power Compact light fixture with out robbing a bank in the progress.
#1 Buy regular incandescent light fixture of your choice depending on your aquarium size. We will use 30" inch fixture just as example. Since this is incandescent light fixture and no one really uses it anymore it can be bough really cheap in your local pet store. I bough mine for 25$.
#2 Now we need to go to the local hardware store and buy our selfs a 2 closet lights. Every hardware store has them. It's a pigtale with a bracket and on/off switch that you usually install in to a door jam.
#3 Bracket that comes with pigtale perfectly allows us to attach it inside the fixture
#4 Buy some screw in power compacts that you can fit in your new fixture and you are really to go. The good thing about this is that you can buy them 2 or 4 at the time saving money.
in 30" fixture I have 2 14W bulbs with 5500K and 2 18W bulbs with 3000K that gives me 64W of power and around 2000 lumen's and over 300 CRI output for around 55$
Could require drilling 4 little holes for the screws or bolts that will hold brackets inside the fixture.
In my opinion there are several advantages to this approach. One is you can put more powerful bulbs in there and increase you wattage, second, is that after everything is done you will end up with 3 power cords that will allow you to simulate dusk and dawn conditions and third is that you can control amount of light your tank is getting.
I will try to post pics as soon as tonight.