Wanted to share this with all the Prospect-D customers and fans and fellow DIY folks. I never knew about this, but I am sure glad to know about it now!  Planning on doing a quarter panel repair on my Mazda RX7 FD 93, Passenger side.  Planning on buying a Spot Welder and amongst doing some researching online, came across this stuff that all of you should know about. 
Refer to the Lord.com website in regards to the Fusor 108B/109B Metal Bonding Adhesive (Medium) and other products they offer: 
The Metal Adhesive is to pretty much glue two pieces of sheet metal together and can be used for extra bonding strength if putting in spot welds. It appears that you can spot weld with the adhesive sandwiched in between the sheet metals. Ever wonder how the factory was able to spot weld with that adhesive rubber sealant left in between the sheet metals? Well now you know.  Apparently some areas on vehicles from some of the factories do not even have spot welds, but instead rely on using this stuff. It also helps prevent rust, so now you dont even have to use weld primer.
This is used from the "FACTORY!!" as claimed by Fusor:
• Chrysler: Weld bonding
• Ford: Weld bonding
• GM: Panel bonding per GM aftermarket spec GM6449G
• Mazda: Corrosion repair
• Nissan: Corrosion repair
In regards to my 240z rocker panel and seat bracket install guides, I highly recommend you put this stuff in if you can.
Check out this Youtube Video by Fusor: