The ornamental design for a reardoorpanel for automobile, as shown and described.
1. Rear door panel for automobile
1.1: Perspective
1.2: Front
1.3: Back
1.4: Left
1.5: Right
1.6: Top
1.7: Bottom
Reproduction 1.1is a perspective view of a rear door panel for automobile showing our new design; reproduction 1.2is a front elevation view thereof; reproduction 1.3is a rear elevation view thereof; reproduction 1.4is a left side elevation view thereof; reproduction 1.5is a right side elevation view thereof; reproduction 1.6is a top plan view thereof; reproduction 1.7is a bottom plan view thereof; the reflections shown in reproductions 1.1are disclaimed.