4point fitted properly to that harness bar would be the perfect angle.
The 3 points shouldn't be fitted then 'pulled' over the bar as they are not designed for that.
Also the rear mounting point should be fitted centrally to the seat they are going to not offset like they are, as in the event of a big crash they are not pulling centrally and can cause a twist.So many people just cheat by screwing them into existing mounting holes rather than fitting new ones.
Thanks for the explanation.