Harnesses
 

So I am trying to think of a way to run 5 point harnesses in my blazer (family trail eater) the reason for this is so that I can run with no doors without falling out lol and for safety I do not have a cage and don't plan on building a full cage is there a way that I can put a shoulder bar or even a kit that is a main hop so that I can have the right set up I may build a custom cage down the road just for low speed stuff like rolling on to the side as there won't be any crazy hill climbs

Most probably not readily available. Should be able to fabricate attachment points thou.
Get pro information about the angles required. The front seats may be a problem if you want to use the rear seats as well.

Riding trails with no door is IMHO not a good idea. Also think branches and such slapping in from the side