i bought the s2k antenna elemnt from honda, but i haven't gotten to put it on yet, because i have been looking for the parts, i know all of the parts i will need, but i can't find some of them especially the #10 coupling, i checked Advanced Auto, Lowe's, Home Depot, so any help would be appreciated!

 

Lowe's should have everything you need, their specialty fastener section blows away Home Depot. But any hardware should have the coupler, look around the area with the 36" and 48" full threaded rods.