benish -
Photoshopping your documents would be forgery, you could be sent to prison for that, and yes, they will find out, if they do proper research afterwards, and the chances that they do that after selection and before hiring you is big, as you also need a security clearance.
I think you should try and see what happens, at least if get nicked you don't need to worry about getting a security clearance in the future!
I do know of guys who failed 2 of their ATPL's, and they did get interview with Ryanair, but they did not pass selection. I also know of guys who partialled their IR, and had interview, by the way they also did not pass selection.
So one thing is getting interview, what happens after I don;t know, the ones I know who got in, all had first time passes, even though I heard a rumour that 90% avr. on ATPL was needed, I do know of guys with much less average who have been selected recently.