feet on the floor during flat dumbell press and incline dumbell press

I’m 5'8" and the benches are high for me. At home I have a bench with leg attachment and put my feet on the rollers on the leg extension attachment. I feel my chest more than when my feet on the floor when I do them at the gym. Should I have my feet on blocks to better postion my chest or have them flat on the floor.

For the best in chest stimulation the feet should be planted on the floor and not on the bench. However, if it is a stretch to get your feet to the floor, then yes, put plates or blocks down where your feet would be for a solid stance and no thoughts about being uncomfortable.