any 6x9's fit without modification?

[325DR]

I know the Pioneer 4x10's I have are 3" deep bottom mounted. I found a couple of 6x9's that are 3 1/4" deep bottom mounted. Will they squeeze in there? I dont want to get rid of the bars and rig anything up. Are there any 6x9's that will fit without doing this? Also, will the adapters make the depth larger (from 3 1/4" to say 3 1/2?)