Ok currently i have prova springs with factory bilsteins but the issue im going to have is with the rears, i plan on towing a 16ft boat which has a total trailer weight of 777kg, now ive towed heavier but the back just slumps too low and tow bar hits in certain places, really want to upgrade rears even higher than factory as i tow trailers every week, someone here must know best option for me, any help appreciated