Pallet lifter 12 volt conversion

[NiftyNev]

I'd like to convert my manually operated 400KG pallet stacker to 12 Volt operation. I have a 12 volt geared motor that is 60 RPM output. The idea is to mount this on some sort of bracket, then make some type of cam to attach to the shaft by boring to motor shaft size and support this with a bearing each end, again in some sort of bracket. The stroke of the pump is 30mm when used with the foot operated mechanism. Anyone have some ideas on how I should make this cam?

[NiftyNev]

It looks like this.

[Noitoen]

I would leave a small length of the actuator arm and use a crank shaft/connecting rod type assembly.