How to mend gaps with stretched objects?

No matter what I try I can’t make the edges of two objects in 2.5D to line up. I tried the trick where you click it with the scroll wheel and hold the “V” key, but since the blocks are stretched, I can not get it to line up no matter what I try. I have a slight case of OCD and it’s driving me crazy! It either has a small gap, or the objects overlap causing the two materials to glitch over top of each other.

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