Some s 10 t5s came with 2 rods that bolted to the 2 holes where a rear mount would be and went down to the 2 lower bolts used to bolt the trans to the bell housing which supported the tail housing with out the extra cross member issue.
I suspect if using a 2 piece drift shaft with a hanger bearing a short distance behind the trans as opposed to a 1 piece shaft it might eliminate a little of the weight that needs to be supported.
To date I've put 3,500 miles on mine without a 3rd cross member with out any issues
