soundhd

Have a 1999 extended cab/4x4/Z-71/LT;67,000miles; A couple days ago started having problems with the third door (passenger side) not closing correctly which causes the regular passenger door not to seal correctly.........seems to have something to do with the upper latch....maybe the bottom also. (third door latches at both the top and the bottom it looks like).. have moved or "rotated" (might be the better word) the upper latch to where or looks like it (3rd door) closes correctly but regular door then does not seal correctly......was wondering if anyone else has run across this problem in the past and what was done to correct it........is there an adjustment that can be made?......if so how is it done?.........trying to save a trip to the dealership if I can............thanks