Welcome to the forum
As others have said, if your cuts are that accurate you are doing really well , As Dennis has said, making sure the chassis is correct in the dimensions is really what to aim for, with strong welds at each joint too,
keep checking the dimensions against the book spec on each phase of the chassis build up & you,ll end up with a really nice chassis.
Enjoy your build & any questions just ask, this forum is a wealth of knowledge in every part of the build.
cheers
andy