I got a new door seal for my car and yeah, it's kind of on okay, it's just not on 100% perfect.

There's the plastic trim piece that goes around the upper 1/2 of the door beside the rubber seal.

Am I supposed to put the rubber in first then the plastic part, or the other way around? Very tight fit in there. Is there some specialty tool to do this right?

Thanks,

jeff W124, 214k