3-m has a product that is bullet proof for this application.
It is Body panel adhesive, which is maufactured to glue two panals
together without welding.
The techhnique to apply would be;
Put a couple of layers of masking tape on either side of the seam, and
with a razor knife, cut out the old seam sealer.
scratch up the inside of the seam as deep as possible with 180
sandpaper, folded in half to get both sides of the seam.
apply a nice even bead, of sealer into the seam.
wet your finger with some mineral spirits and from the bottom of the
panel, tothe top, wipe the seam smooth.
It takes ths stuff about 8 to 10 minutes to set up, so just prior to
being completely hard, remove the masking tape.
You can then wipe the edge's smooth with some more mineral spirits, or
sand the edges with 600 paper.
This seal sealer displaces water,so from the out side any way it will
last.
A good idea, also, would be to seal the back side of the seam with spray
on bed liner. Its a spray on polyurethane, and I used it to seal my
wheel wells, and works good and is easy to apply. Should help keep the
water from coming in from the inside of the seam.
The 3-M part number for the seam sealer is; # 8115, available at any
body shop suppy.

Terry

85 GL
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