Harness mounting points??

[Williams182]

I've got my seats coming this week so wanted to sort the harnesses out at the same time,
was worried about the mounting points, some people have many different views, but many guys state it's unsafe to mount the rear points to the floor, got me thinking... The megane r26r...? Those are bolted to the floor, so I'm happy with doing the same. Just wanted to post this incase any one else is having doubts

 

[loggyboy]

Msa regs say 45 degree is acceptable, but +-10 degrees is preferred.

 

[MarkX]

Also harness manufacturers recommend they are crossed behind the seats if the points are more than 18" from the seat back. I suppose road and race regs differ though.