If you're really fixing it up I guess you'll want to weld it and make it nice.
But I just took an 87 4Runner in similar shape and cut squares around the rust, pop riveted in aluminum, and bondo'ed overtop of that. It turned out solid, with the stiff aluminum backing and the bondo on top.
Make sure you use aluminum rivets, too, or they'll rust and let your sheet pieces loose.
Of course, it's up to you how much you smooth it out over the rivets. I left the 4Runner rough, and put plenty of paint on top.
Won't last forever, but then nothing does. And it was dirt cheap.
Frame is an issue. I'd start laying the oil to it.
But I just took an 87 4Runner in similar shape and cut squares around the rust, pop riveted in aluminum, and bondo'ed overtop of that. It turned out solid, with the stiff aluminum backing and the bondo on top.
Make sure you use aluminum rivets, too, or they'll rust and let your sheet pieces loose.
Of course, it's up to you how much you smooth it out over the rivets. I left the 4Runner rough, and put plenty of paint on top.
Won't last forever, but then nothing does. And it was dirt cheap.
Frame is an issue. I'd start laying the oil to it.