Thanks to you all for a kind welcome... Hopefully I'll be able to contribute something of interest from time to time.
It was while searching for information on Givi top box carriers for the Falco that I first found a thread on the subject here
at ridersite.com. I ultimately came up with a simple system... some say too simple

, that appears to be working
well after 250 miles. (pics below)
Soon, I hope to complete a set of "not so simple" aluminum / HDPE side case carriers for either Givi E 21 or E 360 hard bags.
At that time, I may integrate the top box plate into the side carrier setup.
The heli-bar equipped Falco is surprising comfortable, so all it lacks is a set of hard luggage for some extended mountain touring .
Best Regards, Tom
The Givi top box plate (from a KLR 650) is attached with cable ties at the grab handles, and secured to the Falco's tie-down's using shock cord.
This eliminates the need for drilling either the grab handles or the pillion, and distrbutes the load over two contact areas rather than the pillion alone.
