Close, but I believe the original post says balistik1 will be adding a third MH light...
The other thing to concider is the cross braces on the tank (every 2')
So the same "basic" design but cut at 24" with brackets over the cross braces (no additional shadow effect) and one on each end for a total of 4...
Then unless you switch to 32" lights you'll have a hard time running them "end to end" as shown on a 6' tank...
When I ran my 125/6'...I ran 4' bulbs and "overlapped" them as shown here...
The center is a "little brighter" but concidering the majority of the light comes from the "middle" of the bulb, it pretty well balances out with the "ends" overlapping...
Edit: just noticed you have 2' PCs... Two options here...run three "bulbs" or get an additional "pair"...(second pic)