I've only ordered parts from Motobins once, someone else correct me if I'm wrong, but I think you need to go to the Motobins site, and get their part number before ordering .
What calipers do you have on your LS ?
The early '82's had ATE calipers, rest came from the factory with Brembo's .
Only reason I ask, is that the ATE caliper rebuild kits don't come with the o-ring that goes between the caliper halves you have to order it separately, the Brembo kit does have them .
I've gone to EBC graphite pads, FA18 is their part number, but you have to file the back plate down to get them to fit, if you have an ATE caliper, they fit the Brembo's perfectly .
I can only compare them to OEM pads, and they work way better in wet conditions, than OEM, at least with EBC steel rotors, I don't know if stainless rotors would make a difference .
I've got them on my '84 LS, with stainless rotor upgrade from Spiegler, but the bike is a ways from getting out on the street still .
I installed a set of Spiegler lines on the LS as well, and they appear to be a high quality set .
Also the 'banjo' fittings can be adjusted with the plastic parts that come with the kit, if by chance they don't line up just quite right to the master cylinder or the splitter .
The air horn, will need to be operated by a relay .
You can use the stock wires for the horn, to operate the relay, and then add heavy wire, fuse and relay for the 'load' wiring directly from the battery .
I've been using Metzeler tires ( Me33/Me99-Lasertec) on my '81 R65, since around '87, other than the cost, I am quite satisfied with them .
A lot of members here use Michelin Macadam tires, and are equally satisfied with them as well .
Three of us here have installed a generic AGM type battery, from Staab Batteries ( part number : UB12220), for about $55 including shipping .
Don't know what kind of service life to expect, but I thought I'd give it a try .
http://www.staabbattery.com