if like me your radiator top is narrow with a gap of about 8mm these hooks may  fit . 2 sizes hook 1 is approx 7 mm wide to fit into the grill and then open out to approx 11mm
hook flat widens to approx 17mm wide but can be printed flat

i've added a longer hook , as i needed one to help dry my wet shoes lol 

i printed hook 1 with supports and hook flat without supports
both 30% infill ,just be aware that they may get a little soft if your rads are too hot