I installed a Stormscope antenna on the copilot side winglet, underneath on the fiberglass side.  It's taken me awhile to get the box working, but I finally did.  But I didn't know if it worked until I skirted some midwest T-storms just south of Chicago (ORD) this weekend.

You can see the Stormscope lightening symbols on the Chelton...my first demonstration that the system actually works.  The cross marks are old lightening >1min old.  That's Lake Michigan in the upper right corner, and Fort Wayne (KFWA), Indiana more centrally.

25' special Stormscope antenna cable to the processor in thge baggage compartment.

I have XM weatehr on a PDA with Anywhere Map, and the Nexrad images matched the lightening depicted on Chelton, and did the visual out of the plane.

The wingtip stobe light is not on, but the Stormscope detection actually seems to work when the strobe is ON.  Yes, I was able to see some lightening depicted while on the ground in Nebraska.

Here's the routing.  The angle to the right was to navigate through a break in the storm fronts moving northeast.  FL180.