I've done a lot of work to mine and cleaned the body up a lot but it has too many issues to restore to 100%. It would be easier and cheaper to just buy another truck like you said you plan to do but I like my old truck. I never planned to put a new motor in it but after driving it for 10 years I just couldn't stand to see it die. The body didn't have any major rusted through spots but it had a lot of small rusted out spots, almost every panel on it had some rust.
Since it would never be a show truck I just used body filler on the rusty spots. I'm not talking about gallons of Bondo, maybe a qt with some left over. I figure I'm saving what's left of the truck and in 20 years someone will be glad to restore it. By then what I have would be a good restoration project because all the others will be either gone or someone else would have already restored them.
It looks pretty good in the picture but not so good up close.
