Yeah it's late to clone, I mena think about it, the clones are gonna have to reveg anyway!
If you want to reveg:
-Cut only the prime buds and leave as MUCH plant matter as you can... ALL leaves, popcorn buds, and the bases of the branches the good buds are on.
-Don't let the plant go into that state where the leaves are going yellow from Nitrogen deficiency near harvest. If I had a valuable pheno that I hadn't cloned, I'd be most concerned with the least stress during reveg over harvest weight etc. and start giving her some weak veg nutes. I have never heard of anyone else doing that but it stands to reason when you are trying to convince it to start growing foliage again... I'd personally use fish emulsion for this as it is gentle and organic and I would not expect it to really mess with the flavor of the buds.
Then after harvesting, put it back under 24 hours of light and make sure it is not overwatered, because now you have the stump of a plant that has LOTS of roots but VERY LITTLE foliage to transpire moisture... its water use is going to plummet after you take the buds off, so keep an eye on that.
A repotting into a big pot with nice fresh soil is not a bad idea either.
Good luck, I'm jealous, a good grapefruit pheno is like one of my ultimate dreams!!! mmmmmmmm