I noticed in the Puritan Board search function there have been some good threads on this topic. I realize you are considering it now, lots of people contemplating things for the first time here. The search function is a very helpful resource, especially for some standard topics. Somehow, "infra" and "supra" is one of those topics that regularly comes up here.

You may find this thread helpful:
What does infralapsarianism & supralapsarianism means ?

One observation on the arguments for this: While the divines of the Confessions leaned "infra" (but certainly not all of them), the arguments tend to become circular as one is essentially trying to define time (temporal) against a background of (God's) infinity.