Had the same issue, and I did it myself. It will require silicon adhesive, putty knife, utility knife, and the ability to cut blocks to hold the sink up while the adhesive holds.
In short turn off the water, remove the garbage disposal (phillips head screwdriver, 3 screws, just losen them then turn the disposal) Set that aside.
Take your utility knife, cut the sink adhesive as much as you can then pull the sink off
Remove all of the adhesive on the sink and under the counter top.
Cut your boards do you can firmly press against the sink to the granite underside
apply silicon adhesive to the sink lip
Put sink up and support the sink
Then just reattach garbage disposal and water hoses and turn water on