The easiest way is to get rid of the X-mount, or at least put it on the back of the firewall. Making the holes in the firewall for the center to match up is very easy. I would definitely keep the x-mount on it, but put it behind the firewall to give some extra support. The firewall isn't very thick and spreading the load is a good way to do it. I actually changed the firewall as it was just too thin. We just cut a new one and put it on, spacing it back slightly. It was very easy to do, but if you already have it installed, then just drill the holes to mount the motor directly to the firewall and put the x-mount on the back of it.

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