I'll be dammed - it WORKED
447 MH/s using bitminter just like in the guide. Wasn't sure what the icarus timing parameters in bfgminer ought to be set to, and cgminer didn't seem to want to see it, but at this point I'm just glad I didn't mess up the rework job.
Instead of mining with more hashing power, I like to think of this as mining at the previous difficulty level

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Considering my lack of experience working with SMDs, I basically needed this thread and the tutorial to pull this off. So thanks everyone!