1st does not address the "whosoever".
2nd part if peter meant only the chosen one as you claim, why would God say such a thing as this imply God loses His children which John 6 says He does not. SO you just contradicted one of your Calvinist thoughts That Is once saved always saved which I believe. SO If God does not lose His children as stated in John 6 then why would God say He was unwilling for them to parish, oh you will say God was saying he would not let them, but that is not what its says. I can hear that spirit to, its not Holy.

God would not need to say He was unwilling if none would perish, such a statement implies God's will will not be perfectly done, and why because man has free will to chose and God does not interfere with that.
2Peter 3:8-9 NLT
8 But you must not forget this one thing, dear friends: A day is like a thousand years to the Lord, and a thousand years is like a day. 9 The Lord isnt really being slow about his promise, as some people think. No, he is being patient for your sake. He does not want anyone to be destroyed, but wants everyone to repent.
So its clear you reject the NLT version.
2 peter 3:8-9 NASB(which is the most literal translation btw)
8 But do not let this one fact escape your notice, beloved, that with the Lord one day is like a thousand years, and a thousand years like one day. 9 The Lord is not slow about His promise, as some count slowness, but is patient toward you, not wishing for any to perish but for all to come to repentance.
Ok so you reject the NASB
2 peter 3:8-9NKJV
8 But, beloved, do not forget this one thing, that with the Lord one day is as a thousand years, and a thousand years as one day. 9 The Lord is not slack concerning His promise, as some count slackness, but is longsuffering toward us,
not willing that any should perish but that all should come to repentance.
He does speak of us, those saved but also speaks of the unsaved,"any"
So you reject the NKJV.
2peter 3:8-9
8 But, beloved, be not ignorant of this one thing, that one day is with the Lord as a thousand years, and a thousand years as one day.
9 The Lord is not slack concerning his promise, as some men count slackness; but is longsuffering to us-ward, not willing that any should perish, but that all should come to repentance.
so you say all and any is not reffering to the unsaved you are wrong plan and simple so you reject the KJV.
Lets put it in context.
2 Peter 2 NASB
2 But false prophets also arose among the people, just as there will also be false teachers among you, who will secretly introduce destructive heresies, even denying the Master who bought them, bringing swift destruction upon themselves.
The master who bought them. If the Blood of Jesus did not buy all then who will be destroy? So we see in putting it in context you have scriputre which contradicts its self, John 6 It is the will of God that I(jesus) not lose one of all He gave me. But the bible does not do that. So there must be an error in your understanding. Not in the Bible of the Writing.
Do you know how to put chapters in the Bible in context have you been taught? You read the chapter before and the one after and then the chapter you are trying to understand.
let see what else we find.
2 Peter 2:20 NASB
20 For if, after they have escaped the defilements of the world by the knowledge of the Lord and Savior Jesus Christ, they are again entangled in them and are overcome, the last state has become worse for them than the first. 21 For it would be better for them not to have known the way of righteousness, than having known it, to turn away from the holy commandment handed on to them. 22 [h]It has happened to them according to the true proverb, A dog returns to its own vomit, and, A sow, after washing, returns to wallowing in the mire.
see the part in bold , God is speaking of Knowing the way is Jesus and rejecting God, but wait you say a person can not reject grace, Here God says they can, why say such a thing.
So 2 Peter 2 is all about un believers, so we can not look at chapter 4 as there is no so lets look at 3 again.
So the first part is speaking again of unbelievers and then the end is to the faithful.
The "context" is explaining why God does not end it all ready and the reason is given in 8-9 He does not want any to perish, meaning anyone "unbelievers", you could not possibly get another meaning from that when it is put in context.
Its you pulling it out of context. I just picked peter but really you never made it past John 3:16