BillH wrote:
Here Bob. just an example, shows ram stroke, screw range,etc.

http://www.northerntool.com/shop/tools/product_200304831_200304831

Or, northerntool, auto repair, bottle jacks for all of them

The also have an air operated one @ $59.00

Also, don't know tha dimensions of the tray you are going to set this in but bottle jacks can be a tad shakey. I'd give some thought to tack welding the corners of the jack base to a larger piece of 1/4 plate.