Inverted beam trolley type transmission lift design for home made view pit

Just a design I did on sketchup of an idea for a transmission lift for the viewing pit i dug to work on my truck. I used the pit to remove and reinstall the transmission which had to be rebuilt. I used a similar design that I came up with but it had no rollers. I used two floor jacks on one side and my bobcat skid steer on the other and is how I lowered and raised the transmission. I live off grid and had to use what i had since the nearest home improvement store or automotive parts shop is about an hour away.
just thought id share the design for anyone else who needed something like it for a project of their own. Fyi the Pit i dug was dug mostly by my hands using a shovel and electric jack hammer. the skid steer was only good to remove the top soil, below that is caliche which the bucket just skips along so pretty much used its bucket as a wheel barrow.
dimensions of the pit are 13 feet long x 67inches wide and 6-1/2 feet deep. all walls and the floor were lined with sandbags full of dirt that i ad to fill myself I set four 10 foot beams across the pit , that i made from 4x4's sandwiched between 2x10's which were set into the top soil and placed two 12 foot 2x10's side by side covered with 1/2inch plywood on each side as runners which i drove the truck onto. It worked out well, however i wish i had made the pit longer by 2-3 feet and wish i had set one more beam and extended the runners out further because it was a little cramped working at the ends of the pit. I plan on putting a roof on it and using it as cold storage until i need it to work on my trucks next. for more info or actual video of it let me know in the comments.