I feel your pain, i had to install more memory for my old pc, so its still alive even after a bunch of power outtages and random turn offs.
I treat her well so she knows to come back to life.
(joking its a machine.)
What you could try to do is cut this up right now into different files say about 4 or 8 and each piece is a section of the character and when you save it at the final at the end you can puzzle piece it back together.
(it is a possible work around so there is that, options)
gl