I've never had an Isuzu with drum brakes, but I have had a large number of other vehicles with drums.

There "should" be a rubber plug on the back of the mounting plate that will probably be an oblong shape. If you take out the plug, you can use a brake spoon to back off the brake adjuster all the way.

You can then take a rubber hammer and hit the drum all around. That should break loose the brake (pun intended).

Jim Paget
88 YJ with a few changes

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