Well I ended up using the polyester based resin. I can see where there would be a problem attaching something to the SMC if it wasn't damaged because the smooth surface of the SMC doesn't provide much to grip to.
I kept the car even while using 2 jacks on the frame to tip the car them set the tires on blocks to hold it up while working on it. Safety first, I try to keep anything from having a way to fall. I've had a couple buds get crushed. Yes the wheels were also chocked on the other side.
The resin seemed to stick very well to the roughed up surface and I had no problems making a solid floor. The floor on the other side of the car is rotted out in the same area where this one failed when the tire hit it. Car has gasket issues and carpet was rotted out in the lower outside corner. Maybe someday someone will fix the other side? Here's a couple pics of the job in case someone else finds this thread searching for a floor fix.
Tip it up and lets get this party started!
The damage
Door striker section plastic piece, sill carpet piece, and plastic piece by gas pedal have to come out. If you're limber the seat can stay. Peel back carpet sections and tuck out of the way.
Cut away broken section and ground SMC to give the new resin something to grip. Also helps prevent a "lump" transitioning from original SMC when overlapping with new fiberglass matting. Along the tunnel where the crack was I opened the crack wider with a hacksaw blade so resin could fill the inside of the crack and adhere to matting above and below.
Made a cardboard form below to catch any drips. I haven't powerwashed the driveway since I finally finished moving in but I don't want to make the job any harder!! Resin is a pain if it gets a good hold!
Laid up and ready for some rough contour sanding.
A little paint to make it pretty. Wet in pic, dries flatter and with a couple drives on rainy days it'll blend right in.
Straightened out the mangled shield and pop riveted it back where it was originally.
Cleaned and reinstalled carpet and interior pieces. DONE! Slowly lower car evenly.
