Tangram Puzzle "Pentashift"

This is a 3d tangram puzzle I designed for my father's birthday. It took him over seven hours (cumulatively) to solve it, how long will it take you?

IMPORTANT: NO PARTS MUST BE FORCED IN PLACE OR BROKEN, AND THE PUZZLE MUST BE SOLVED IN THE SMALL BASE. ALSO, ALL NUMBERS ON THE PARTS MUST BE FACING UP.

You can print all the sections at once if you have a big enough printer using the allpartsatonce file, or you can print the lid, base, and parts separately using the three other files labeled