Been doing remodel and new framing all my life, don't know that I'd use a 2x10 for 8' span

Sounds a bit much even for supporting a roof only overhead, what about if there is another floor above that? I only use 2x10 for up to 4' span, 2x12 up to 6' span, then LVL, Microlam, Paralam, or whatever you may call it. Shoring wall aut to be 2x4 across the room with studs a minimum 24" oc with "X" bracing nailed across the stods to stiffen them (Can not tell you how many times I've seen temp walls rack because someone miscalculated the load that would be on them, so the cross bracing really helps)