Remove your seat and using the original bolts screw these as far as they will possibly go..this cleans up the thread ready for the seat pins.
Lay the seat on take a measurement from frame to top of seat plastic….then assemble the pin with the nut first and star washer , you should be able to set the rough height required using the previous measurement. factor in the height of the self-adhesive black rubber washer that is to be stuck on the seat the metal washer goes between the rubber washer and r-clip .
Please note: after feedback I have been told you may need to clearance the seat base a little with a round file or similar as seats vary across the years
Lock down the nut once the height is set ,aim to align the hole so its easy to remove and refit the r-clip, you can also use some thread-lock to ensure the pin doesn’t move.
This is pretty much the same as above but getting the pin height needs to be more precise. Too high and the tank wont go down ,too low and you cannot insert the R-pin.
You may have to remove the steel inserts in the rubbers and re-insert once the tank has been lowered into position. It all depends on year of bike. Also some people have cut the rubber in half leaving half on the fitted pins and remove the other half when lifting the tank. If after lowering the tank the pins do not line up anywhere close to the pins the rear tank mount may be loose or have shifted, or your tank is swollen if a plastic model .