As you can see these are bound to [1][2][3] whereas I use scrollwheel to select weapons.

DRAW VIEW MODEL
bind "1" "slot1; r_drawviewmodel 0"
bind "2" "slot2; r_drawviewmodel 0"
bind "3" "slot3; r_drawviewmodel 1"

VIEW MODEL FOV
bind "1" "slot1; viewmodel_fov 90"
bind "2" "slot2; viewmodel_fov 30"
bind "3" "slot3; viewmodel_fov 90"