I finally broke down and bought the HF Pittsburgh Bead Breaker, Harbor Freight item 92961. (
I used that harbor freight bead breaker to break the beads on four difficult steel-rim wheels with Optimo P235/75R15 108T thick-sidewall tires seemingly glued on.
After using it successfully (not without a few curses), I conclude the HF standalone bead breaker sucks but it sucks differently than the bead breaker attachment on the Harbor Freight tire changing tool.
The HF tire changing tool bead breaker is fine for the three passenger tires I've done now, but it's far too weak (puny would be more apropos) for the strong sidewall SUV tires.
Luckily (as Clare kindly warned me), all of what sucks in both tools can be "fixed" if you know ahead of time what to modify (as Clare has kindly shown us):
What sucks about the tire-changing tool bead-breaker attachment is: a. The bead-breaker arms are too weak (and bend like a pretzel) b. The clevis pins (thanks Clare) are far too sloppy (replace with bolts) c. The bead breaker arc is far too small (about 1/2 to 1/4 of what you need d. The tire iron twists out of your hands (use a vise grip to prevent that) e. The tire iron is too soft so it bends when used as a lever (use pipe) f. The base *must* be bolted down for SUV tires which require turning force HF Pittsburgh Bead Breaker, Harbor Freight item #92961
What sucks about the standalone bead breaker tool is: a. The base is far too short for big tires b. The base has no attachment holes for securing to concrete or pallets c. The lever action isn't all that powerful (but it's strong enough) HF Pittsburgh Manual Tire Changer, Harbor Freight item #62317
Here is the first method that I used as an expediency to temporarily "extend" the base of the HF bead breaking tool (it was a steel shelf from a Costco shelf rack):
Here is the second method that I used to extend the base (it's just a board of wood that I had lying around):
I changed multiple car tires easily with both tools, but SUV 108T P235/75 tires stressed both tools to the max - where - without the emergency modifications above - I don't think you can do the job (I couldn't).