Last fall I ordered a pair of "Dirt Baggs" 39L aluminum panniers, black w/ 'beveled' lower outside corner, along w/ a set of GiVi pannier mounts, and they came after we got to AZ.
This spring I mounted up the mounts, then tried to think up w/ a way to attach the panniers to the mounts. I had a couple of ideas, then saw a pic in "Members Rides" that showed how he'd mounted his. Asked the question and the answer came back - Happy Trails, so I ordered the mounts from them. Unfortunately they were out-of-stock, so it took a bit over a month to get them (last Thursday...).
So-o-o, Friday morning I started the install. I had had a friend sit on the bike while I figured where the bags should go, so I took a piece of chalk and marked a few "hard-points" for the left one which I then put onto the workbench, then removed the mount, placed it onto the bag (face down).
Next I took the "Handyman's Secret Weapon" (duct-tape) and attached mount to bag, taking note of my chalk marks. Then I attached the Happy Trails pieces to the GiVi mounts so I could use a center punch and GENTLY tap the center of each hole. Removed the mounts, put a 1/8" bit in my drill and drilled a pilot. The Happy Trail mounts use the metric equivalent to 5/16", so I chucked up a 5/16 bit and made the final holes, de-burred them, then re-attached the GiVi mount and the bag. Looking GOOD! NEXT job - do the same for the right bag.
I'd hoped that I could just lay the left bag over the right one and mark the holes w/ a pencil for the alignment. NO such luck (manufacturing tolerances?), so I repeated the process as above till it TOO was mounted.
So, Saturday AM I went for a ride to Home Depot to get a four-padlock set, keyed alike, then over to Princess Auto (our version of Harbor Freight) to buy some LED tail-lights for the rear of the bags. BIG, I want BIG, so nobody can say they... "Didn't see me..." Also (probably over-kill), I got some 3/4" clamps that I'll add one or two of to each side in the unlikely event that a mount vibrates loose - this way the bag STAYS attached.
The LED lights I bought are 7" diameter w/ 31 diodes, capable of running lights, turn sigs AND brakes, but w/out another part (like when you attach trailer lights to a car w/ separate turn and brake lights) you can't just tie the brake and signal function together.
I figured that mounting the lights centered, but low on the cases would work, and leaving my OEM signals also in the circuit would negate the need for a special LED flasher (LATER I'll go that route, changing my front signals to LEDs), so I held the 7" lights to the rear, marked the holes (they are 1/4"), then drilled a 1/8" pilot for each and decided that I should go a "bit" over 1/4 so I went UP by 1/32", and drilled the holes to 9/32", giving a bit of 'wiggle-room' in the event that my holes weren't perfect.
Attached everything and got out my electrical stuff. Ultimately my plans are to wire it differently (wires INTO the bags, then out near the top mounts w/ a waterproof plug so the bags can be easily removed when necessary by just unplugging the wires, etc.), but for now I used 'taps' to get the power from wires under the seat, and put dis-connects inline so that I CAN remove them even if it takes awhile
Turned the key to ON - WOW!, then put a signal on - double WOW!!
This wouldn't work for those of you who are 'minimalists', but I want these to be "IN YOUR FACE" so everyone, even the 'texters', see me!