I thought i would lay down my experince of mounting a Bestem 929 Top Box onto my 1996 ST1100.
I purchased mine from Cruiserback rest on EBAY:
http://www.ebay.com.au/itm/ST1100-Bestem-Top-Box-w-Backrest-Trunk-LED-T-box-BLK-/110721972438?pt=Motorcycles_Parts_Accessories&hash=item19c78b38d6#ht_1436wt_905It arrived in a matter of days, I purchased mine from the USA, but they had one in Australia, so i got it quickly, and they refunded me the difference in the freight as well, so i was very happy with that!.
after unpacking it, i laid it out on the bench as you can see below in the photo, the 2 brackets on the left i think are for mounting on a scooter, i didint use them but i made use of the 4 bolts and the mounting bracket.
I started by making use of my mate across the road who has every tool known to man in his shed, it was quickly apparent that this brack would need some adjustment to be strong and effective, especially on the rear mounts as it lines up you have to drill though the plate where it is folded for strength, so we welded in some flat plate on both sides.
after lining up the appropriate holes, we decided against adding anything at the front as it would not have the stress the rear would have, I strongly recommend using a dril press or to drill your holes as it is very easy to make a mess if you are not careful!
when we mounted it we thought it best to use sleeves on the bolts as it made it very simple to set it ad the right height, we just used the sleeves that came with the gearsack rack that was on the bike when i bought it. i have tilted the back up slightly so the back rest comes into play for Teela on the back.
After that is was some killrust to make it all pretty
and you can see below the end result, very neat and tidy, and it is not going anyway where!
below is before and after
for what i paid about $140, i think it is very good, it happily holds 2 helmets or a spare helmet and bits and peices, i didnt bother hooking up the brake light.
Cheers
Streak