Great video. If you look closely at the engine you can see the large oil lines necessary for the full flow oil filter on the truck 261. You cant remove the oil filter and plug the lines on the truck engine because it wont get oil and will seize quickly.

I knew of a few of those big trucks in my area many years ago. One was a tanker and the front suspension wouldnt take the weight. GM offered a kit that consisted of a leaf spring that was bolted to the bottom of the crossmember and the ends of the spring sat on pads mounted on the lower control arms.

Paul