DON"T use velcro... after time, the velcro will start to wear out the seatbelt. I have heard of it from a bunch of JK owners and they said that it happens quickly (months, not years). Big safety issue if you ask me. I would just get some seat belt pads (the ricer type r ones
or if you want to be cool, just plain black).
I have also heard of people placing the seat belt behind the pillar in 2drs only. I have not looked at it yet, but I plan to just to see.
The last option I heard was placing foam or any carpeted surface on the pillar.
The seat belt pads seems like the belt way since it is hidden between the seat and pillar.