Hello and welcome to BYC!

Glad you joined.
I'm going to be
that person...
Those guides are just that, very loose guides.
I have raised chicks out in a coop when temps dipped into the low 20s at night. Those chicks were not kept in an environment where some or even most of the area was 95F. They had a brooder plate with an old bath towel thrown over it to make a cave. When they were chilled, they darted under the plate. When they warmed up, they darted out to pig out at the chick feed trough.
I've had a batch of 8 chicks under a hen in the coop during a big, blowing snow storm, again in the 20s.
Watch the chicks. If they are huddled together as close to the heat source as possible and cheaping loudly, they are cold. Lower the lamp.
If they are sprawled out and lethargic as far from the heat source as they can get, they are overheating. Raise the lamp.
On the subject of lamps, they are intense and hard to control and you cannot turn off the dang light! Brooder plates or mommay heating pads are far superior and safer heat sources. Obviously a hen is best. You need to be careful trapping too much heat in those metal water troughs.
ETA: the neat Flir thermal image of a fully feathered hen vs roughly 2 week old chicks to clearly demonstrate that those fully feathered pullets do not need that heat source.