It will be another couple days until I can call in to Meade. I just realized that my cell phone is in our house quarantine right now after a trip to my doctor's office yesterday. Due to our age and individual conditions, we are following a strict family protocol during this Corona Virus shut down. When I can get my phone back, I will give Meade a call. I am not sure if they are open or not since there is a shutdown in progress in the Los Angeles area.
I do not have any information on the allowable weight on the rear of an LS 6, but I do have some thoughts:
1. The original attempt by Meade to put LNT detection in a scope failed because of residual magnetism in the steel tubes of the AutoStar LNT scopes. When they produced the LS scopes, aluminum tubes were necessary to avoid the same problem. Be sure to watch and see if your magnets affect the positioning of your scope when it is finding magnetic North (or maybe South).
2. Weigh the added equipment, subtract a little for mirror and eyepiece the scope would otherwise use. You will have to estimate to the best of your ability the distance between the altitude axis and the center of mass of your additional equipment, and likewise the distance from that same axis and the center of the spot you would attach weights. The amount of weight needed to balance your added equipment should be the extra weight of your equipment times its distance from the altitude axis divided by the distance from the axis to the position of your counterbalancing weight.
Hope this helps!