Download the GTA V FoV v1.35  Google it.
Install it. Then you MUST edit the settings in fov.ini
Remove everything and replace it with this:

; If you only want to change certain fields of view,
; comment out the others by placing a ; at the start of their lines.
[FirstPerson]
;Walking = 68
Car = 69
;Aiming = 64
;Crouching = 66
;ADS = 60

[ThirdPerson]
; Some people have reported issues with changing the third-person FoV,
; so it is disabled by default.
;General = 68

[General]
; If you want to use another mod based on dsound.dll, you can rename it,
; uncomment the line below (remove the :wink: and change other_dsound.dll to the name you gave it
;ProxyLibrary = other_dsound.dll