These are some measurements for taxidermy forms, the largest is nose to base of tail is 51 inches. flexible tail is 27 1/2 inches. Eye to nose is 3 1/2 inches. girth is 36 1/2 this is probably a old thick cat about the same proportions by the look of the form.
African lion is 80 inches long and tail is 36 inches , eye to nose is 7 1/4
I dont know if its doctored or not but theres no dout it is beefy cat.