1. Height: Measure Top to Bottom on both the left and right sides
2. Width: Measure (L-R) Top - Middle - Bottom
3. Measure for door jamb to door jamb
4. Looking from the inside, which side would you like either the motor or hand crank to be loaded?

If you have any questions on how to measure we will be glad to assist you in any way we can.

(You will loose 8" of headroom on Jamb Mounts only)