mopar65 said

I would just buy the right mounts and then you don't have to mess with the extra washers. 318 mounts are spaced different compared to 340/360 engine mounts. Here is the stock replacement mount.
https://www.oreillyauto.com/shop/b/.../v/a/2379/automotive-car-1975-plymouth-duster

Here is some performance mounts thst should last a very long time. But you use your factory outer mounts

https://www.oreillyauto.com/shop/b/.../v/a/2379/automotive-car-1975-plymouth-duster

Click to expand...