when I said Thrash, I meant sensibly lol
lightly warm her up with a gentle drive, have a look for leaks, (best do this bit at night) get onto a dual carridge way into 2nd or 3rd and briskly but not drag race to half rpm and snap the throttle shut, let it coast down and do the same accel again a few times.... then go for more revs and higher gear.
this process pushes the piston rings to bed in properly and also heat cycles the pistons nicely.
that method aside, the general rule of thumb is to NEVER labour the engine in any gear, and never really hold much of a constaant speed either (until later into the process when you can hold x speed for a few minutes to get the heat in and ensure its all well).
OEM purchases are pre run in from the engine plant, and then again from the assembly factory, the only thing you need to bed in is the tyres lol
