Here's how I do it. It's pretty easy. I'll post the steps here with pictures. You should have no trouble doing the same. It takes less than two minutes to get the angles perfectly matched.

Preview with your Main Camera. Set it for a wide angle focal length. I usually use 20mm.

Load your environment sphere.

Depending on which way your lights are it may look dark and hard to see.

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Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)