The question shouldn't be weather its OK to get gross body piercings and tattoos, but weather you have crucified your flesh with Christ through repentance and are walking in the spirit, because if you are, then your question would be irrelevant.
Its simple to answer your question, but many will not see to understand why a real follower of Christ, will be dead to the world and all its vain attractions, so the piercings and tattoos, are just the tip of the iceberg in the apostate worldly church today.
You can really gage where a persons heart is when you tell them these vain worldly practices and not of God, you can argue day and night how these things are Grey areas in the Bible, then make many excuses why you can be like the world and still be saved.
I urge you to get into the word, repent unto salvation as Jesus commands, crucify your flesh with all its passions and desires, flee from the lust of the flesh, the love of the world, and the pride of life, then your eyes will be open to why your question is a straw man excuse to be a lukewarm Christian.
The church is supposed to be an example of holiness, seperation and purity, a separated people zealous for good works, not copying the vanity and idolatry the world offers!
1Jn 2:15 Love not the world, neither the things that are in the world. If any man love the world, the love of the Father is not in him.
1Jn 2:16 For all that is in the world, the lust of the flesh, and the lust of the eyes, and the pride of life, is not of the Father, but is of the world.
1Jn 2:17 And the world passeth away, and the lust thereof: but he that doeth the will of God abideth for ever.
1Co 6:19 What? know ye not that your body is the temple of the Holy Ghost which is in you, which ye have of God, and ye are not your own?
1Co 6:20 For ye are bought with a price: therefore glorify God in your body, and in your spirit, which are God's.
2Co 6:17 Wherefore come out from among them, and be ye separate, saith the Lord, and touch not the unclean thing; and I will receive you,
2Co 6:18 And will be a Father unto you, and ye shall be my sons and daughters, saith the Lord Almighty.
Jas 4:4 Ye adulterers and adulteresses, know ye not that the friendship of the world is enmity with God? whosoever therefore will be a friend of the world is the enemy of God.
2Co 7:1 Having therefore these promises, dearly beloved, let us cleanse ourselves from all filthiness of the flesh and spirit, perfecting holiness in the fear of God.