i wouldnt go the maddat if you can make it your self ,all you need is a welder (mig) and some 5mm plate

i used a standard ute cross member and i cut the mounts of ,then i used my jig to set the mounts up and then weld it up ,i think i have some pics of the mounts the jig

and the S13 X member wont fit and niether will the 4x4 X member