Well, once I got to the river Saturday morning I pulled the boat out and installed the 2131 5 blade. I ended up only having 3/8" clearance between the prop and the hull so I pulled it and installed the 1235 which gave me 5/8" clearance.
I'm guessing maybe the pitch of the prop made the difference? They are both 14.5" props. Anyway, the 1235 worked great and was an absolute beast out of the hole!
I emailed Jim at Acme but he told me he would be out of the office until tomorrow. Here's a pic of the 1235: