Chassis dolly/casters?

gong to make like a chasis dolly. so that the entire car will be on casters..
I believe i want to attach the rear casters to the front leaf spring mounts.
trying to figure out some different ideas of how to attach some casters so that I can roll around the entire car.
i won't have a rear end or leaf springs on the car. and the engine and tranny are out of the car. also front end is out of the car..
I can weld too..