Body Seam sealer

[JALFAjr@domain.elided]

I have a 1971 GTV and need to know what works for sealing the gas tank/spare
tire frame to the rear quarter panels.
It appears to be some type of flexible petroleum product that spaces and sort
of glues the frame to the body panels.

Would a good silicone sealer work, or should I use an actual body shop seam
sealer which contains limestone of all things?

Also, what works for the gasket material between the gas tank and the body?

Any suggestions would be appreciated.

John Justus
1971 1750 GT Veloce
1995 164Q

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