Position of right arm when tapping?

In Chris Berry's "Two hand tapping of Scales and Modes (part1)" He suggests using finger 123 of each hand to tap out a scale or four notes per string. When using more than one finger for tapping scales such as in the tutorial mentioned, where should the right (tapping) arm be placed to make for easiest/fastest tapping.

http://www.guitartricks.com/2000/trick.php?trick_id=3079

Further to the above question, what should be done with the tapping hand's thumb.

And where does the plectrum go? :)

Check out Schmange's home page. There's about 50 pages of kewl stuff related to tapping.

Oh great thanks, does look cool,