Most of the mods (and theres alot of em) are home brew.
The Tank is an IMS 4gal made for a honda xr650. The shape fits well, but the mounting points dont work without some fab work. The stock rubber pucks where replaced with some pvc pipe end caps that I wrapped with inertube rubber. Then I used 1/4 threaded rod through the frame to hold them on. The rear mounting point I bent a piece of aluminium into a upside down U shape. That fit over the frame and bolts to the top engine mount. Its worked without any problems for about 5000 miles now. I get between 225-250 miles to a tank depending on my riding. The xr tank has a brass insert to hold the front of the seat down. This isnt needed on the Sherpa and just plain looked like hell. I used the mounting point to screw a cheep fannypack to the tank. It hides the poor seat to tank fit and I get a tankbag For under $20.
The Tailrack topbox and heatshield Kind of slowly morfed over time. The tail rack started as $15 worth of 1/8th inch aluminium I fabed up to hold a small motofitz bag. I really liked the motofitz exept its not waterproof. So i came across the box at colemans military surplus. Its a surplus aviator nightvision system box. $30 plus shipping. Great size for a topbox, holds a case of beer. (cube shape) Mostly I use the box for comuting crap then to hold my riding gear while im at work. The box comes with 6 compression clamps, I removed 4 and added hinges. As a waterproof test I filled it with 33 liters of water and doesnt leak. Good enough for me.
I added some straps inside the hinges to hold the lid while its open. And some tiedown points to the top. The mount is a dove tail cut in a plastic cutting board pined and paddle locked. Hope the pics help explain.
I liked em so much I put 3 on my DR.
The heat shield I added this spring. I use them to strap 2 sealine bags to the bike for a trip to Arkasas. Again I bent the aluminim and added the tiedowns. The rear tiedowns just go around the bag, the front goes from one heat shield around the bag over the seat to the other heat shield. That puts most of the wieght on the seat.
I had to move the rear turn signals. Aluminum is my friend.
The toolbox is a pelican box. Same mounting spot as factory.
The windscreen was just a scrap of acrilic I had in the shop, with a old piece of fuel line around it. Its adjustable and in the up most position it pushes the highway air blast up off my chest to the top of my shoulders. Thats all I wanted. Pre windscreen 71mpg was the best the bike ever did. I got as good as 81mpg with the screen. Im 6' 2" tall about 200lbs with gear. I think just getting all that air off my chest made a BIG diferance.