Sure. I think if you look Biblically, santification and justification are used synomonously, both in the past and present tense.
So, as proof that justification and sanctification are the same thing I'll quote two verses. You will ask for more, but I would ask that before you do that, please come up with
explicit evidence that justification is
different than sanctification. Because, if you cannot, then you fail by your own standard (i.e. my Bible does not explicitly say this or that.)
Proof 1: 1 Cor 6:11
Such were some of you; but you were washed, but you were sanctified [hagios], but you were justified in the name of the Lord Jesus Christ and in the Spirit of our God.
Proof 2: Acts 26:18
I am sending you, to open their eyes so that they may turn from darkness to light and from the dominion of Satan to God, that they may receive forgiveness of sins and an inheritance among those who have been sanctified [hagios] by faith in Me
Proof 1 shows that the words are used interchangeably and all in the past tense. (FYI, "justified" is used in the continuous present tense in Rom 3:24, Rom 5:1, Rom 5:7, and Titus 3:7 in the Greek, you can read the KJV and it renders all four as "being justified.")
Proof 2 shows that Jesus is sending Paul to "open their eyes" which "by faith in me" results in "forgiveness of sins" and that those with faith would be "sanctified." The fact that the word "Sanctified" could easily be swapped out with "justified," and mean the exact same thing, shows that if we simply take the Bible at its word and not impose any theology on it that the concepts of sanctification and justification are identical.
SO, THAT BEING SAID, my proof for "our righteousness is being indwelt by the Spirit" is as follows:
Do you not know that you are a [f]temple of God and that the Spirit of God dwells in you? 17 If any man destroys the [g]temple of God, God will destroy him, for the [h]temple of God is holy [hagiazo], and
that is what you are (1 Cor 3:16-17).
So, in plain English, the dwelling of the Spirit is what makes us holy. If being holy is the same as being just, then we made righteous by the indwelling of the Spirit. This indwelling occurs when we have faith in Christ--we are completely credited the righteousness of God, because we are indwelt with the righteousness of God. It is not a legal fiction as 1 Cor 3:16-17 makes clear. If we persevere in the faith, we maintain this same righteousness by the grace of God.
I hope this addresses your question