A method of assembling a door on a vehicle begins by identifying critical fit areas between the door seal and the door frame. Pressure indicator tape is adhered to the seal in critical fit areas and the door is closed against the seal to produce a marking on the pressure indicator tape. Intensity of the marking is visually compared to a reference pressure intensity scale to establish an observed pressure intensity level. The observed pressure intensity level may be recorded, correlated to a specific critical fit area and analyzed to make operational and design improvements to the door, door frame or seal.