Was there an "STD" Crx?...and if so...is it mechanically the same as a Civic STD?

This manual that I have found says that it is for a 91 CRX, but is comatible with most 88-91 Civics. It refers to STD/DX being lumped together and the Si/HF being lumped together for example,

23-10 Engine Wiring Harness - STD/DX models
23-11 (photo)
23-12 Engine Wiring Harness - Si/HF models
23-13 (photo)


So does that idicate that the STD and the DX are the same...or just for that part?

Jason