I'm installing a Speedway bolt-in IFS on my '50 3100. I have jack stands under the front of the truck near the firewall. I don't have any under the rear of the truck. The frame rails are perfectly level in multiple measurements. The crossmember reads the same, i.e., clamped in place. Given my measurements, is it necessary to put stands under the rear before drilling holes to mount the crossmember? If yes, school me as to why.
