I just finished rebuilding my forks, and part of my upgrade was to add New Bonneville Gaitors from Bella Corse. Since the job is fresh in my mind, I thought I would help you out with a detailed description:
Things you'll need-
1- Bike needs to be jacked up enough to remove the front wheel and forks. I have a Sears Professsional motorcycle jack that I got on sale which works well. I'm not sure if the centerstand would be enough clearance, but I doubt it. Others may have this answer.
2- You need a 6mm allen hex head to loosen all of the pinch bolts, a 12mm allen head hex to remove the axle, and a 12mm socket to remove the fender and the brake caliper. You'll also need a torque wrench that can do 20Nm and 60Nm. A phillips screwdriver with a round shaft is just the right size for slipping through the axle passage so it does not spin when loosening and tightening, and it is also used to remove the speedometer cable. I used a wire tie to attach the caliper to the chassis to keep the weight off the hose. Some grease and some WD40 or equivalent is also used.
What to do:
1- With the bike raised and supported, remove the plastic caps that cover the hex heads on the two lower spindle pinch bolts, the four bottom yoke bolts, and the two top yoke bolts.
2- Remove the speedometer cable screw and disconnect the cable. This can be passed backward through the wire loop once you remove the caliper to keep it out of the way.
3- Remove the two caliper mounting bolts and remove the caliper. Attach it to the chassis with the wire tie to keep it out of your way, and the weight off the hose.
4- Remove the axle spindle bolt, and then loosen but do not remove the two spindle pinch bolts. Support the wheel's weight and remove the axle, noting how the speedometer drive assembly lines up to the dog on the left fork, and the bearing sleeve sticks out on the right side. (All L & R references are from the driver's seat)
5- Remove the bearing sleeve and the speedometer drive and put them and the wheel in a safe location.
6- Remove the front fender, noting whether yours uses the spacer washers between the fender and the forks (don't ask

) There are also two reflectors that come off with the fender.
7- Loosen the top and bottom yoke bolts, and twist the forks out. Since you are not rebuilding them, I would do one side, install the gaitors, and then reassemble before doing the second one.
8- Wipe down the fork shaft with a clean cloth and some WD40 or equivalent (I used an Amsoil product). Slide the gaitor, fat side down, onto the upper fork and then spray some WD40 or equivalent around the boot top and work the boot up and down. This is per Bella Corse's directions, and prevents the boot from sticking or binding, and also helps to displace moisture in the boot, to prevent corrosion of the fork. Don't worry about the wire ties for the boots yet.
9- Twist the fork carefully back into place, and tighten only the top yoke pinch bolt to 20Nm. My Legend has the top of the forks flush with the surface of the top yoke face. This is also true for the T-Bird, TBS, and Adventurer according to my manual.
10- Do the other fork leg the same way, again only tightening the top yoke pinch bolt upon reassembly.
11- Put the fender back on, not forgetting the spacer washers if it had them(Again, don't ask me why

)
12- Wipe off and regrease the end of the bearing sleeve and insert into place, and then line up the speedometer drive into its correct spot, with the ears lining up. Check this by turning it and watch the little tit inside the tube where the cable attaches. If the ears lined up correctly, you'll see this turn as you rotate the drive housing.
13- Raise the wheel carefully into place without dropping either the bearing sleeve or the speedo drive. Insert the axle and screw in the spindle bolt, making sure the speedo drive is behind the tab on the left fork tube. Torque it to 60Nm, then torque the spindle pinch bolts to 20Nm.
14- Reattach the brake caliper and the speedometer cable, torqueing the caliper bolts to 28Nm.
15- Lower the bike to the ground, sit astride it and holding the front brake, force the forks to compress two or three times. Then tighten the lower fork yoke pinch bolts to 20Nm, and replace all the plastic caps over the pinch bolts.
16- Rotate the boots so that the printing, etc., is out of sight, and then put on the wire ties, again hiding the parts that stick out as much as possible.
17- You are done! Easy, wasn't it?
A couple of notes - I always remove any bolt that I am using and spray it with an anticorrosive product (I use Boeshield T-9) to keep it from getting nasty in the future. In some cases, never seize is fine, but I hesitate to use that around brake rotors. Some claim that never seize can also affect torque measurements. The Boeshield product does not, and I have used it on my firearms, including my semi auto pistols for years, and it works well without building up. I got some of the Dupont spray teflon to use on my chain, and it looks like it would also serve well in this application. I got in the habit of doing this many years ago on all my cars, tractors, mowers, etc., and it makes future disassemblies a piece of cake.
Bella Corse recommends armor all or something similar to protect the boots on the outside. Theirs are butyl rubber, so you may want to check with the type you are using before using anything inside or outside.