Yes there are some good threads on here if you search. I am doing it as well. I am keeping my YJ fenders. Issues .... there may be more than this...
1. CJ fenders have to be trimmed to fit around the shock tower. If you use YJ fenders then you will have holes to fill in where the hood latches were and where the YJ grill used to bolt to.
2. CJ grill has to be trimmed on the back to fit around power steering lines.
3. The radiator/grill middle body mount must be extended to line up with the frame.
4. A 1" body lift helps with the grill and fenders and hood all lining up. The CJ grill is like 1" taller than the YJ.
5. If you keep your YJ radiator then you must fabricate a way to attach it to the CJ grill. I am using a CJ radiator so it bolts to the grill no problems
6. My clutch fan ended up like 1/8" away from the radiator so I am using an electric fan so now I have wiring issues to control the fan.
Remember the JEEP DOMINO EFFECT...
...every mod you do requires several more
Here's how mine looks so far.