To purchase the most suitable engine for your blind should know the weight of it. If you need help, contact your dealer to get that information. If you do not have this possibility, you can choose to put a scale under the blind to get your weight, this adds value + 20%. That way you will get a ballpark figure of how much it weighs the blind.
Then, start by analyzing the pipe model where winds the blind, so you can get the engine accessory equivalent to the tube format.
Finally, the engine installation is quite simple, you just have to fit the engine into the pipe and connect the motor to the electronic central to make the programming of the end-of-course.