When you splice a replacement panel or a portion of a replacement panel to 
an existing panel, use the following procedure:
- Clean and inspect the damaged
area. Refer to 
General Plastic Repair 
.
 
- Cut the damaged area and/or the
replacement panel to the appropriate size so that the panel fills the opening.
 
- Scuff sand the damaged area and
the replacement panel's mating surfaces.
 
- Fit the panel to the opening:
 
| •  | If the bonding strips are exposed, mechanically attach (1) and bond the
 strips together. | 
 
| •  | If the bonding strips are not exposed, cut or grind the edge of the panels
 in order to form a good butt joint (3). Then bevel the edges (2) to about 30 degrees
in order to form a dished butt joint. | 
 
- Install
 a backing patch (3). Refer to 
Backing Patch Fabrication 
 .
 
- Following the manufacturers instructions,
mix and apply a light coat of the repair material to the outside of the damaged area.
 
- Lay a piece of reinforcement mat
into the repair material.
 
| •  | The mat should extend 38-51 mm (1.5-2.0 in)
 beyond either side of the repair area. | 
 
| •  | All of the mat must be at a level below the final finished surface. | 
 
- Using an applicator, saturate and remove any trapped air from the repair
 area.
 
- Apply a second coat of the repair
material in the same manner.
 
- Lay a second piece of mat into
the repair area in the same manner.
 
- Apply
 the final layer or repair material in the same manner until the repair material 
(1) is at a level slightly higher than the surrounding area.
 
- Cure the material according to the manufacturers instructions.
 
- Apply and cure additional layers as needed.
 
- Rough out the surface using a #80 grit disc on a D A sander.
 
- Apply
a polyester type material to provide a uniform surface for sanding, such as Sikkens®
Polystop LP, or equivalent.
 
- Prime and refinish as necessary. Refer to the GM Approved Refinish Materials
book GM P/N GM4901M-D which identifies the paint systems you may use.
Always refer to the latest revision of the 4901M-D book. This operation is to be performed
prior to the application of sealers, waxes, deadeners, and antirust compounds. Follow
the procedures recommended by the material manufacturer.