Hey I'm installing a moen cartridge for the first time and having trouble with getting the retainer clip back in

I lightly toothbrushed the faucet with a mix of vinegar and water and let the water run thru to make sure the cartridge would go in all the way

But it seems like I don't have space to fit in the clip

It's supposed to go thru the slit part of the valve, right?

This is the same clip that was in with the old cartridge (also moen 1222), I unfortunately didn't take pics while removing parts

Should I cut the tile above? I feel like that's a bit extreme, but I think a plumber we had before knocked out a whole block in another shower, maybe because it was like this

Thanks for any advice and Happy Holidays !

I have this moen single handle shower valve in all my bathrooms so I've had to replace one of these 1222 cartridges before which was a nightmare for me. It took me all day trying to pry that thing out using Moen's cartridge removal tool. So this time when I had to do another one, I decided to buy the Flowrite ONA cartridge puller so it would be easier. Long story short, it was fine I got the cartridge out quickly, but the back end broke as you can see in the photo and I had to dig that plastic piece out of the valve. I oriented the cartridge as recommended by pointing the notched end upwards before removing, not sure it makes a difference? Is there something I'm doing wrong? Not sure why these always give me trouble, I couldn't imagine being able to pull one of these out without a removal tool of some sort.

Help, please!!

I got an aftermarket Moen 1222,, and a very nice puller, from Amazon. Problem solved on pull out the old one. (Previous project was another story.) But the new one can't get in the last 1/16 inch!! Then one side rubber piece was damaged when I tried to pull out. Now at Lowe's and buying the genuine Moen one with a small tube of waterproof grease.

My question, what is the best way to smooth the inside of faucet, to make the new cartridge go in smoothly? Using steel wool? I used very fine sand paper before, and caused leak, on project years ago.