I installed the Lancair marker beacon antenna and it works fine.

 

I'm not sure how long it is but I know it's less than the length of the baggage compartment in my ES.  I punched a hole in the forward baggage bulkhead and located the antenna connection forward of the bulkhead under the elevator torque tube.  The copper strip ran back through the baggage compartment with a 2 bid over it.

 

Photos attached.

 

Mike Easley