Nice, Scott! Actually, a pair of later model K75 bars is a common swap, probably akin to a pair of Norman Hydes.
Their charging systems were often under-rated and an upgrade alternator is widely available.
That bike uses a dual pull cable throttle, a bit different than our SOHCs.
Use www/bobsbmw.com website for the parts fiche.
Corbin or Sargent both make repro seats that bolt straight on, the Corbin Gunfighter Dual or Canyon Sport would be a great option.
Wagons are a very common swap and upgrade to the rear shocks.
The center stand is desirable to reinstall, so you may have to revert back to stock side stand.
I see an aftermarket oil cooler on there too.
A couple of places to service:
The speedo cable rubber housing into the transmission case. Prone to leaking water in- check and replace/fill fluid for assurance.
The output/input shaft of the trans/driveshaft needs regular lubrication.
Theres a special tool for the exhaust flange removal, if you don't have it, get one (or I'll loan you mine) to service any exhaust gaskets.
These bikes are set up pretty lean from BMW, slightly enriching them really turns them on
Specialty wrenches are required on some parts to service them. You'll find tapered bearings stock in the swing arm and steering head!
Bimmer forums or airhead.org tend to be pretty good places to get info.
Non-stock color that Canary Yellow for that year (I'm pretty sure). Would look great in the Daytona Orange!