if you have a three speed in it now you don't need a crossmember the bellhousing has the mounts on it like a 55-57 chevy car.
if you have a truck 4 speed you use the same bell housing. just have to use bolts and nuts in the bottom two holes as the tranmissions are tapped and the bolts go in from the front.
if you have an automatic you use that crossmember.