Trying to tan hides into leather with acetic acid, lye solution or ammonia. Which is best?

I have skins with the the meat and fat all scraped off the inner sides and all hair removed. Times past I've tried bark chips (tannic acid) and brains (which stink). I'd like to try something different. I have three solutions to try, but I want to know if anybody has had good results with them before. I have acetic acid (about 20% solution) crude lye (potash) in water (about 20% solution) and ammonia (about 15--18% solution.) If you have ever tried these before, please tell me which is best.

Please only answer if you have experience making leather from hides, I could speculate on my own.

Please no complaints about the animals, they were found already dead along the vehicle trail used by reforesting crews. I have to dispose of carcasses to prevent attracting scavengers and spreading disease. The hides would otherwise be incinerated and wasted.

Thanks to all who contribute helpfully!