It depends on what you want. If you want a S10 with an antique body then the body to frame swap is right for you, but it will always be an S10. On the other hand, if you want a street rod then keep the original frame, or a replacement of the OEM frame, and build your car from there with aftermarket parts. You can obviously save some money with the new frame approach, but if you are trying to build value for the long term then setting the old body on a new frame is not going to be a good value proposition in the future. My $0.02, and others may disagree.