I do a lot of work on a stone driveway and it sure does suck. I put 3/4" plywood down when I can't move the vehicle. I don't always have any,but it's worth the investment even if you buy a sheet just for one job. Last summer I swapped axles between my 3/4t 4wd Suburban and Jimmy. Fortunately I had a job coming up replacing the roof on an old spring house that took 6 sheets. It took three to shuttle the axles to the vehicle beside using Harbor Freight dollies under the drums/discs. I just installed the plywood dirty side up on the spring house
. I have a 4L80E/NP241 combo to drop out of the Suburban and have about a 30" wide piece of pressure treated 3/4" I've kept around to lay under the jack. My big floor jack is about impossible to push under anything w/o being on plywood. If at all possible this summer,once that Suburban is junked I'd like to "finally" pour a slab there. The concrete outside my shop (sorry,no vacancy) is taken up for parking another project. It would be a real luxury if my next place is a shop that have a house,or at least a place to eat,sleep,and wash up. To all who have to work on vehicles outside on dirt or gravel,I feel your pain. Sucks,don't it? Ya gotta have a sheet of plywood around. I also have an ancient piece of carpet I roll out to lay one. I have spent more time looking for dropped hardware in loose stones than it takes to install it...if I found it.