looking good, ive got a gorilla zkittles at 5 weeks, looks very similar , huge fan leaves. Ive just tried out a method of topping i saw on yt once , where this guy pulled apart the top most small leaves then rolled around the new nub of growth till it came away, apparently it puts less stress on the plant and it doesnt pause the plant like they would if you snip off the tops. dont forget you can foliar feed at this stage to boost it along , diluted nutrients , they love it.
apparently its called micro topping ,

Looks like you got at least 4-5 nodes now. You can top it on the 4th node.

I always cut my lowest branch off , they always seem to stay small and unproductive , and i noticed last grow that if you have a thin stem and an even thinner branch off that, it wont get enough nutrients and you end up with popcorn bud. so i am snipping all those off on the lowest part of the plant.
ive got a feeling you are going to have a lot of huge fan leaves so that bottom one won't be getting much light , you could try rooting the cuttings as well then you would have 2 more plants.