T5 DIY planning.

[sphelps]

If you really want to save a couple more bucks you could skip the waterproof end caps and use standard ones which usually cost about $2-3 per pair. These are used in Tek and other fixtures. You can protect them with a shield or periodic cleaning. You can also apply a little silicone around the bulb ends and meets the end caps, when replacing the bulbs the silicone tends to stick to the bulbs rather than the end caps.

You'll also obviously save more money skipping the WH3s and using another WH5.

Good call on the 48" reflectors, I do the same thing. You will have to either get extra bulb clips or simply screw the reflectors to the fixture or canopy.