Magnificent gun-and that's some superb wood graining on your Target grips; my Security Six came with the Target grips, but I found them to be a tad speedloader unfriendly, so after experimenting with a set of Hogues I ended up with a set of Trausch TJ84R grips, modified for me by Jacques Trausch (with the grip's butt cut to fit the Security Six's square butt, and the left grip thumb ridge reduced and given a crescent cut to better allow for speedloaders).
There's something both rugged and attractive about your later-production Security Six, what with the heavier barrel and right side recoil shield scalloping-you've got a great piece. Let us know how it shoots!
Best, Jon