Trying to get to the 1890's wood floor under 2" of subfloor+

I have been trying to remodel my late grandparents 100 yr+ farmhouse for the last month. By myself. It's a huge undertaking to say the least. Long story short, I've discovered the kitchen has a beautiful --and by the looks so far, pristine wood floor way down deep. I haven't a clue what species of wood it is. Walnut maybe, but not hard enough. Anyway, as I was digging into the lumpy linoleum that is currently the top layer, I found a 5/8" plywood subfloor stapled to the floor beneath, which I thought was the wood floor. The more I went into the room (foot by foot) I found another layer of bright blue vinyl tile, tarred (black sticky gummy crap) down to another 5/8" sheet of plywood, nailed with varying sized nails to the desired wood floor, and in some places, likely 50-70 years ago someone attempted to shim low spots with more tar and plywood veneer. Further still, I found another layer of a weird floral papery vinyl type flooring just laying there. The desired wood floor was protected, sanded, and waiting to be uncovered. Of the four people "supposed" to be helping me, I am the only one doing anything and the only one wanting to get down to original. It took me _several_ hours to get 30 inches into the kitchen. Each layer was nailed or stapled like a hundred times in each square foot. How can I get through and remove each layer without damaging the beautiful floor 2 inches down and not take weeks to get it up? I am extremely handy for being a chick, but not experienced in subfloor removal. or at least not one of this depth, adhesion, and importance. What handy tools should I acquire? I used a circular saw to get through the 1st two layers of plywood once it became 2 full layers. That was slow and tedious. I had to use a chisel and multi tool to get up the veneer and tar at the door way. It was a strange sandwich of numerous materials likely found around the farm. Then pry and pound down, remove nails, repeat, pry, pound, pull. There has to be something faster or at least more productive. Please some advice! The photo attached is the same floor material I found in the dining room and living room under carpet. It also was tarred and sanded before being covered up, but not sanded well. The kitchen actually looks to be in better shape.