How to add shaker motor to a system 11b

[gunner007]

Looking around kits are around $400 to add a shaker to an older system.
Is it possible to add the spooky shaker kit to a system 11?
I'm thinking it would be awesome on Whirlwind.
The storm is coming!

 

[gunner007]

Anyone know of a good inexpensive replacement for a shaker motor?
I found one $30 amazon for a massage chair but it was vibration than shake.