How much lift can install or Do I need the CV to run at a high angle?

Keep in mind that 1310 CV drive shaft will flex to about 30 degrees prior to binding. If you need to have more than this, We suggest that some machining and grinding work be done to the CV prior to assembly. This will typically allow for about 35 degrees of flexibility to the CV prior to binding. This additional grind work adds $70.00. It is generally suggested to have this work done on TJ applications having more than 5-1/2" of lift either a long arm kit or a belly up kit or any TJ application having more than 6-1/2.of lift.

Please refer to this link to help determine if you would need or benefit from this higher flexibility: Slopes VS Angles

Remember too that this procedure will allow the most flexibility possible. There is a possibility that you may still experience a binding problem in certain circumstances. After installation of the drive shaft at the transfer case end, proceed with the following test: Jack the vehicle up and let the suspension hang freely. Check to make sure the drive shaft will connect to the pinion and still rotate by hand with no binding. If this occurs, We recommend that you place a single limit strap directly over the center of the differential. This will still allow for a near full wheel articulation but prevent the entire differential from dropping to the point where you would experience a binding problem with the drive shaft.