1. Remove brake rod free play adjusting nut (14 mm), freeing brake rod from brake drum lever.
2. Remove axle nut, loosen drive chain tension adjusters.
3. Raise rear wheel off ground.
4. Slide axle forward, loosening drive chain; remove drive chain from rear sprocket.
5. Remove hitch pins from axle retention pins, pull axle retention pins upward to free axle.
6. Slide axle rearward, remove brake shoe assembly from drum.
7. Remove brake shoes (brake spring plies recommended; locking pliers, screwdrivers, punches, etc., have their limitations for this procedure).
8. Clean residue from drum, using brake cleaning fluid and rag.
9. Install replacement brake shoes into place on pivot pin and cam, grease activation cam and pivot pin.
10. Reassemble rear hub assemblies in reverse of disassembly, adjust rear brake pedal free play with adjusting nut, but—do not fully tighten rear axle, aligned correctly with drive chain tension adjusters. Spin up rear wheel and apply rear brake sharply, allowing shoe lining to center itself in brake drum. Check axle alignment, tighten rear axle nut fully, insert axle cotter pin and ride on!
Truth be told, my own KLR250 brake shoe replacement story has no happy ending, YET! EBC brake shoe cam contact surfaces were too wide to fit between cam flanges (about 11/16" wide, vs. OEM 5/8" width). Shoes would not contract sufficiently to enter drum. May have an appointment with Mr. Bench Grinder tomorrow to address this problem (i.e., grind cam contact surfaces so brake shoes will clear drum when at rest).!
In contrast, the old OEM brake shoes shown below have clearance to fit within the cam flanges, allowing contraction to insert the brake shoe mechanism into the brake drum: