A little more thought on this. The sockets (acquired from the $7 clamp-ons from Home Depot) have a 1/8" pipe thread where the wire enters the back of the socket. This is the standard pipe nipples you can find at the hardware store, lighting departments, etc. You could put a small corner brace in each top corner. Drill a hole through it and use locknuts to attach a pipe nipple to it. Thread the wire through the nibble, and screw the socket onto the nipple for a rigid socket which should be oriented in the right direction for a full size plant, no flexible goosneck extender. Just thread the reflector onto the rigid-mounted socket.
Use the extenders for smaller plants.
I like to distribute the total required wattage as much as possible (some from the top, some from the side). The problem in your case (if you don't use strips) is that you don't have the space for typical lightbulbs on the sides. You can get these
inexpensive "bulbs" made of SMD5730 strips. I have a few and wouldn't normally recommend them because the product page isn't accurate, they only draw 3-5w. For the spaces I grow in (2x2x4' tall is the smallest) that's not feasible to rig up that many bulbs.
However, in your case, those would be ideal as sidelighting. Mount a socket in each corner and use the shortest flexible goosneck extender to put the bulb right into the leaves. Let it omnidirectionally feed light to the leaves. I don't believe they'll burn the leaves because they're such low wattage, they don't get too warm. Stick 'em into the plant like a mind probe.
You could do Cree A19 9.5w (60w equiv) on the top (4 of them) and 4 of the smallest strip-light bulbs from the sides for a total of about 50w.
Those strip-light bulbs are so cheap, you can buy one of each to compare. I have a few of each. (I gave some to one of the forum members a few months ago.). From what I saw, the only difference between the larger and smaller bulbs is number of LED chips. The watts used didn't rise by more than 2-3.
BuyBay is another seller.
That's how I would do it if I didn't want to rig up some 12v strips, dimmers, etc. A total of 8 sockets. Four of the smallest Cree bulbs in reflectors from the top corners (using flexible extenders as necessary). Four of these low-wattage "corncob" bulbs penetrating into the leaves, lighting inside the plant, no reflector.
In addition to the link to how I use Crees (in my first post above), a photo in
this post might show it better. The difference is: you wouldn't mount them on the ball-swivel. You would use the common pipe nipple to mount rigid from the back of the socket.
