What lava stream layout will disable a blaze spawner?

Question

...or what layout is shown in the upper right? I can't quite decode the positions at which the glowstones are placed relative to the spawner.

I have a working xp grinder based around a blaze spawner in Nether. Now I want to build a wither skeleton grinder, but two most convenient crossings are located practically out the door of the blaze grinder chamber. And of course spawning blazes will completely overwhelm the skeleton spawns.

I saw a video with a smart way of toggling the spawner through placing four dispensers with lava buckets on the roof. The four lava streams, when flowing through the spawn area keep it lit enough that no blazes can spawn. But the video glossed over the dispenser locations too, not giving any angles good enough to determine just where they should be. It's almost certainly the layout in the upper right pic, but I really need to be sure - this being survival, I'd rather avoid punching unnecessary holes in a blaze spawner room ceiling.

Answer 1

These pictures look a bit old - on previous versions the spawning area was 8x8x3 centered on the edge of the spawner.

In current versions it is 9x9x3 centered around the center of the spawner. Blazes need light level of 11 or less to be able to spawn. The idea in all of the above pictures is to maintain light level of 12 or more inside the spawning area. The light decreases by one with each block traveled. Glowstone (and lava) are light level 15, the adjacent blocks are light level 14 etc.

Armed with the above, we can now construct the following:

Lava dispensers are at the 4 marked locations and are facing down. The spawner is in the center. Lava will make a plus sign when flowing form a downward-facing dispenser, that is why there is a plus sign of light level 15 and then on the rest of the blocks light level decreases but is still above 11.

Answer 2

I can see any of those working fine, as lava gives off a light level of 15, and the maximum light level blazes can spawn in is 11, so the upper right corner one will work fine

Answer 3

Up right would work but make sure the lava doesn't flow in a cross. It would make the lava go away a lot slower when you activate the farm! Therefor use dispensers with a bucket but put them up by one block above the ceiling so there is a one block hole. This will fox the lava making a cross.