Thank you all for the encouragement. I believe my Trini is having four babies, the vet said one more might be hiding in the x-ray. Wow! and I thought she would have like 1 or 2.

I used a small saw that i bought at Target along with a very smooth & sharp kitchen knife to get around the edges. It was kinda difficult but doable and well worth it. To smooth some of the roughness off I bought a very fine sand paper and gently rubbed the edges smooth. Whew!! It took less than an hour in total.
I put 1 pee-pee pad and two medium towels in there, do you all think that is alright? Sorry for all the questions, I am so nervous and this is my first doggie litter ever...
Thank you all again!