Make sure they are all on the same amount and they are facing straight.
If one side of a ring is on more than the other, then the filters will be hard to get on. You have to get them on enough for the glue to hold. Mine are just before they can't go anymore. They will hit the nub on the carb.
I used a straight edge across them to line them up before the glue dried.
The filters go on the part that is machined. (they will stop at the raised ridge)
I had to clean up the inside of the filters a little to get the burs out. If they don't go on easy, you can heat the flanges up with a heat gun and slip them on. Don't over tighten them.
If you do a search you will see pics of a few installs.
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