Glad to see another Suburban going back on the road! Some things to consider when putting this back on the road, most likely it will be more powerful and faster. Consider reinforcing the way the stock seats are attached and allow for seat belts. Some have installed three point seat belts in the front, be careful when making your connection that the material will hold an impact.
One thing that I am going to improve on is the front jump seat, It does not have a catch system to prevent it from going forward when you slam on the brakes, something that concerns me. I have looked at later model seats from blazers and Jeeps and will attempt to make a system similar to those and other two seaters.
I would check with an upholstery shop for what type of modern materials that they can use to make your seats more comfortable on long trips. They may use new springs and then install a moulded foam and material on top.
Have you checked into using modern seats with the integral seat belts? Lot's of manufacturers have gone to this style and I considered them too. I have seen the later suburban front buckets and rear seats installed and they look nice. there are lot's of them to choose from, including material or leather.
If you choose to use the original frames in the front. If you are tall, consider moving them back a few inches if needed for legroom. I have not seen this but I will make that determination when I get mine that far. The front jump seat may be a problem if it does not move forward enough to let the passengers in.
Good luck and post some pictures!
