How to you pin/mark your favorite (gtr cab) mic position?

this:

[ame]http://www.amazon.com/5mw-650nm-Laser-Module-6x17mm/dp/B001B44KAA/ref=pd_sim_dbs_t_4[/ame]


and then this:

[ame]http://www.amazon.com/Map-Dot-Stickers-Diameter-Red/dp/B003M6W0BG[/ame]



*i don't think the talent that comes into our studio would like chalk-dust or whiteout smudges on their $5k duesenberg.