Try Golf club head weights. These are low tack relatively low profile and readily available.

Don't expect any big differences-----unless your A/C is consistently dropping to the same side (time after time) in loops, pulls to vertical etc. lateral balance means little----VERY little!

There is a tremendous amount of misinformation on this subject-------published here as a matter of fact------it is simply wrong.

Don't believe me????

Try this qoute from Chip Hyde---http://www.rcuniverse.com/forum/m_2388583/anchors_2472166/mpage_//key_/anchor/tm.htm#