This is my novice opinion if your car is a dedicated race car already at 135mph then you would need a thought out full cage anyway. So cut out those fenders not for weight savings but for efficiency on wrenching on the motor. Instead of J-bars have the cage extend through the fire wall.
Not sure whose car this is grabbed off the internet but it paints a picture of the room you have and actually with the straight axle you have even more with the removal of the shock tower. Very lean and easy to work. It’s no fun racing with cramped engine compartments.
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