That's a good starting point. If you go DIY, you can use ballasts meant for the 4 foot 36 W tube. However, there's also an electronic ballast that some LFS carry that has 4 pin sockets sticking out so the PLL tube can be connected directly without the need for any additional wiring. Using this makes the job simpler but it does mean that the total length of the whole thing will be longer than your tank.

Make sure you get the 6500K Cool Daylight tube (865) and not the warm white ones.