This is my first thread and i know there have been many, many others who have started
one on this very same topic - but am so excited about this mod
i dont recommend this to starters as the power is unecessary if you are still
hovering - but for agressive/3D its a must!
bought secondhand Eflite 20amp ESC and Eflite Park370 Inrunner Brushless motor w/8Tooth pinion = 30bucks! [hooray 4 ebay]
i dont have a pro version and this is how i did it

1) soldered a spare servo lead on to channel 3 [just black and yellow wires - dont need red bcos ESC is powered from battery]
2) put motor in [which is so light and small you think its guna be pants!!!]
3) connected ESC lead to 4in1 [used paper clips to join as both connectors are female and wrapped tape round]
4) made a Y harness from battery to 4in1 and ESC
5) away you go

the power is fantastic and if you get into trouble you can just blast off away from tree/ground etc
have dual tail and have to say it performed admirably
because mine is secondhand the ESC had been setup so if anyone else has good settings for this speed control please post!
i will be 'trying' tictocs/low 'e' loops[am ordering spares now!] - so look out for vids near future

WARNING - the brushless 'arms' real quick but the tail esc/gyro in the 4in1 takes longer so if you do this and
forget to wait for the tail your guna be doing some advanced piros quicker than you intended!

this has been so useful and am always forgetting so im guna put this here
THE CHANNELS - [taken from previous post]
1 left rear servo
2 front servo
3 main motor ESC
4 tail motor ESC
5 is unused [but is gyro adjust on PRO]
6 right rear servo

im goin flyin' - thanks for reading MG