h1 extension while pending i-140

[em401]

I would like to ask you a quesiton that I am having. I have a pending I140 (niw) which was submitted in Mar 08. In the meanwhile, I need to extend my H1. I was told that I have to check a box in the form indicating I have a pending I140. Has any of you done it before? Can you kindly tell me which box/question it was? I tried to find it, but could not. Thanks a bunch, and have a wonderful weekend!

 

[nightsman]

em40a1: it is the question that asks something like have you every tried to immigrate and to give details. you have to provide your case no.