you can't mount the 4 speed the same as the automatic because the manual trans bell housing uses the crossmember mounts and the 4 speed doesn't have any tail mount, it hangs off the bell housing .... if the cross member was removed [usual for the conversion], you'll need to replace it regardless whether you use the front or side engine mounts .... if the 350 has the front bird legs and they're not bent, then the truck wasn't ever used hard, the distance between the bird leg mounts and the automatic tail mount is waaay to long to withstand much stressing, especially with a manual/clutch setup [car 3 speeds have a tail mount]
Bill
