So I have already built this reactor once before, which is about 2 blocks underneath the one I am building. However for some reason when it comes to this second reactor, it is telling me that only "Reactor Casings" can be placed and gives me a coordinate, I go to the coords and it takes me to this granite block that is inside of the reactor. I tried replacing it with a casing even though I knew it wouldn't work and it said the same thing and put the graphite block back and looked all around the reactor making sure I didn't miss-place something, I found no such thing. However I did pre-maturely place some stuff for after it is built like chests on the input output blocks and a wire connected to the back, so once I removed those it told me a new block which was the location of my gelid inside of the reactor. What am I doing wrong here?



![ReactorOverview](https://user-images.githubusercontent.com/32960618/138613537-9dc4acec-bc51-4611-8022-18f2d202ab


45.png



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for some reason it didnt post the overview, so here it is:

I have figured it out. the blocks underneath full blocks such as graphite blocks and fuel rods, it needs to be the regular reactor casing. I didn't know that was a thing, but perhaps it was one of those "common sense" moments.