In chapter seven Paul is describing a Christian at war with the carnal nature but when you get to chapter 8 especially verse 2 you see that Paul here says that:
Romans 8:2 For the law of the Spirit of life in Christ Jesus hath made me free from the law of sin and death.
8:3 For what the law could not do, in that it was weak through the flesh, God sending his own Son in the likeness of sinful flesh, and for sin, condemned sin in the flesh:
Romans 6:6 Knowing this, that our old man is crucified with him, that the body of sin might be destroyed, that henceforth we should not serve sin.
First notice in chapter six it says the body of sin the carnal nature might be destroyed. That is pretty strong terminology and pretty explicit in my opinion and then the verse goes on and shows it is not speaking of a time at death or glorification because it says that henceforth we should not serve sin. This is speaking of while we are alive we can have our carnal nature removed!
Now by way of illustration lets substitute the word CHAIN for the phrase LAW OF SIN we would then find Paul saying he was bound by a CHIAN in chapter 7 and freed from a CHAIN in chapter 8. To say therefore that Paul meant he was given the power to overcome and resist the CHAIN but not have it removed would be the same as saying that by loosening the CHAIN to where you could hobble around was freedom. Such an idea makes no sense! If someone is bound by a chain and them set free it means the chain was removed from them and in no longer on them! In just the same way when Paul says he was freed from from the law of sin that he speaks of struggleing with in chapter 7 it means the same thing that it was removed and he no longer had it! Otherwise why did he not say " the law of the Spirit of life in Christ Jesus hath helped me with the law of sin and death rather than freed me from the law of sin and death.....
As to how I deal with the scripture that you posted from
1 John 1: 1 John 1:8 If we say that we have no sin, we deceive ourselves, and the truth is not in us.
1:10 If we say that we have not sinned, we make him a liar, and his word is not in us.
In order to understand this verse I look at these other verses and compare them together and in comparison it shows that he is speaking in a past tense of someone before salvation saying they have no sin and therefore no need for the blood of Jesus look and the following scriptures:
(All from 1John)
2:1 My little children, these things write I unto you, that ye sin not. And if any man sin, we have an advocate with the Father, Jesus Christ the righteous:
3:6 Whosoever abideth in him sinneth not: whosoever sinneth hath not seen him, neither known him.
3:8 He that committeth sin is of the devil; for the devil sinneth from the beginning. For this purpose the Son of God was manifested, that he might destroy the works of the devil.
As to my body being still desiring sin though that us not sin itself I also would not call it blameless but Paul says our body can be blameless:
1 Thessalonians 5:23 And the very God of peace sanctify you wholly; and I pray God your whole spirit and soul and body be preserved blameless unto the coming of our Lord Jesus Christ.
Now as to weather or not the swirl of Christ did anything to our mortal body as in a change of standing to dead because of sin and only the spirit alive. Please notice these two verses also from
Romans 8:
Romans 8:10 And if Christ be in you, the body is dead because of sin; but the Spirit is life because of righteousness.
8:11 But if the Spirit of him that raised up Jesus from the dead dwell in you, he that raised up Christ from the dead shall also quicken your mortal bodies by his Spirit that dwelleth in you.
Here we first see a Christian whose spirit has been revived but they still have a body of death but in the next verse we see a Christian that through God has had his body revived also! Therefore to say that we must continually near about a dead body of sin all of our life is fallacy.