LOL ... loser
yes they are road legal, well depends what ones u get but both normally pass an MOT,
Yes you can keep the normal set belts
4 point ones you should mount on a cage or welded in rear stut brace, or bolt in to the originl seat belt mounts in the rear. or drill some holes for eyebolts
Drill holes for eyebolts for the lap belts or bolt into original seat belts points/ seat subframe