.... OR... you can often redrill the engine mount holes to move the engine forward a bit.

This will have little affect on the C.G. if any, as you'll only be moving the engine forward a tiny amount.

At worst you may end up having to buy a new mount, but this is easier than having to deal with other options...

It is better to have the mount firmly affixed to the firewall instead of on washers, so that it spreads lateral loads out over the entire wood surface.