77 FJ40 Brake Booster question...this is an easy one

[ColoradoFJ40]

Is there suppose to be any kind of seal or gasket between the back of the booster and the firewall? My 40 looks like it has adhesive residue but I can't find anything saying there is one.

Thank you
Mark

 

[reddingcruiser]

No gasket, usually just rust back there

 

[nuclearlemon]

May have a paper piece between them, to keep corrosion/rubbing against paint down, but nothing acting like a seal