I usually wrap the head in a old sock (i find a sock traps a bit of heat while still allowing the head to breath) then heat the engine with a heat gun to 100-110*C then let it idle on the box for about 5mins, then shut it down check the piston is off TDC then let cool.

Then I do 3-4 5min runs around my back yard with the sock in place and preheating and cooling the same as with the first tank, constantly checking that the engine is keeping the heat at about 100-115*C, while doing this i load the motor up but do not let it rev to high and slowly increase the RPMs dont blip the throttle.

Once that is done i take it to the track (prob best to remove the sock before you head down the track though) And basically tune the engine over the next 3-5 tanks while not letting the engine hit peak RPM down the straight till prob the 4th ot 5th tank.

It should be all sweet by that stage, but if the engine still seams tight keep running fuel through it till it is ready to tune. We are very lucky with Neals motors cause there is no 5-8 Ltr run ins and generally speaking the motors are ready for full race conditions alot sooner and there isnt the strain on the internals with his hand lapped piston and sleeves!. With the hand lapping they are probably ready to go sooner but I believe that a few more tanks can not hurt.

I hope this helps, this is the best method i have come up with, i have always had great results from this method, and have never had problems with my motors.