You understand salvation better than most Charlie, likely you have read about the coming Kingdom Mat 6:10, and how death will be cast into the lake of fire Rev 20:14, but I am thinking that you may not understand the time period sir. The Bible indicates that for those of us who have inherited the earth, will have to be tested, as was Adam and Eve who failed and put us in this position. It will not be until after the millennial reign of Christ that satan will be released to tempt us Charlie. It is very easy to understand and clearly states that. Rev 20:7,8. Notice that the born again Christians who went to heaven gained their salvation, actually immortality when they were resurrected to heaven, as you stated and recorded for us at Rev 20:6, but for the rest of us we do not gain life until we undergo that test, that is why verse 5 stated the rest of us do not come to life until the thousand years have ended. It makes perfect sense Charlie.
You already understand that salvation does not come until after death so far, but for most of us we will not have it until we pass the test, then satan and those who fail that test will be cast into the lake of fire, and the death we inherited from our original parents will be gone forever Rev 20:10; 21:4. Hope this helps sir.
Another thing that you mentioned is knowing we have salvation, the truth is, we cannot know, there would have been absolutely no doubt in Judas mind that he was saved, he was personally selected by Jesus to be his apostle, what a privilege. No doubt until just before he traitored Jesus, he would have thought he had it in the bag. Everyone is basically righteous in his own eyes according to Pro 21:2 and both you and I think we are saved, and we both think the other is not. But looking at the Bible as a whole, we know that when we signed on as being one of God's people, we signed on to be obedient for an eternity Charlie. When we leave God, He will leave us. It was nice touching bases again Charlie, and thank you very much for your kind comments sir.