clutch

i have a single cam and im pretty sure the tranny is dx and its hydro since the car is dx but my clutch started to worn out and i decide to replace. didnt have alot of money so i bought a used one since i dont have a job till next week. i got it and the guy said he took it off his single cam hydro too of his crx. the clutch didnt fit it was slighlty bigger then the one i had. i didnt know cause i bought the clutch first and the starting to take the car apart. but was wondering did he give me a wrong clutch? or on d series tranny they dont all share the same clutch? and it doesnt fit because the pressure plate doesnt go on good, and doesnt let does thing on the flywheel go on those little hole on the pressure plate.