Here's the idea, we'd take the Maxima front wheel drive engine, transaxle, and suspension and build a cage around it. Then we'd cut a hole in the floor of the car and drop the unibody down onto that assemby. Finger out where it all needs to attach and, voila! Just that simple! Yes, I know, they are never that simple!

As for the earplugs, I used to carry two pairs of ear muff type hearing protection thingies in the Chickenhawk for just that reason. It was uncomfortably loud in the driver's seat, not quite as bad in the passenger seat, and somewhat civilized sounding outside.