Installing a basement door - Who has done this before and has tips?

Hello

I am currently installing a door in the basement.
The opening in the masonry for it is extremely tight. I already had to shorten the frame a few millimeters at the bottom. Now the frame is in, but there is only 3mm space to the wall. How am I supposed to get foam in there? The sleeve doesn’t fit in there.
Does anyone have tips?

Steven

Well, just enlarge the opening or try using an EPDM sealing tape.