I don't think there is a simple way to do it. Its probably best to take the plate off and remove the seal, and this will allow you to properly seat the new seal in the plate with eass.
If you do this, there is a hard to find gasket that goes on the front plate. This helps seal the water.
So in the files section here on the website, you can print out the front plate gasket onto paper, cut it out. Lay it on the front plate to ensure the proper size. Then trace it onto felpro material and cut it out.
Then use a skim coat of grey rtv when you put the gasket on the plate and reassemble.
https://mazdaminitruckin.com/make-your-own-gaskets/
