Be very careful. Those bolts go straight through the suspension strut.
You can spray them from underneath, I would spray them from above as well.
There is an art to removing these bolts; undo slightly, then tighten back up. Repeat this process for atleast 5-10mins for each bolt, each time you loosen slightly, give it a bit more before re-tightening.
If you spend time doing this you will not snap the bolts...