Normal break in procceedure is more about seating the piston in an ABC engine. With the used engine I would just run it rich for a tank or two (I always run my engines slightly rich even after break in)
I follow the OS procceedure on my TT engines. Start engine, tune to high rpm for 5 seconds turn 1/2 turn rich for 20 seconds, reapeat and slightly increase high rpm time as you go for two tanks, then run rich for the first gallon of flying.
Some people just run a new engine rich and fly right away with no problems.