Here in texas we have what we call "diminished value" it is the price between trade in of your car the day before the wreck, and the day after you receive the car from the body ship repaired. My old 2012 ram 1500 was hit with 78 miles on the ODO. No joke, by a 17 year old girl texting and driving. Good thing I was raised right as if it were a teenaged boy he would be dead. 35k dollar truck went down to a 22k dollar trade in. I received 11780 and some change, check in hand for the diminished value. ONLY possible because the accident was NOT my fault. Some states have this and some don't. This can be claimed ontop of what ever else you want. If they decide to fix it and you want to get rid of it, or what ever keep this in mind.
Your best bet at keeping the motor would be to just find a FUBAR 5.0 stock block and throw it in there and give it to them before they total it. At the end of the day, I feel bad for you as I have been following your build from day one. Even before I picked up my 5.0... It's sickening and horrible to know the hard work and money into this car and to have it ruined. No way you're going to get all your money back. I would be surprised if you got over half back... One small thing can set you back years bank account wise...
I had a bad curse I recently broke with this new 5.0. I had 3 new vehicles in the past 2 years an f150, a ram 1500, and a new HD sportster. All of them were hit by somebody texting and driving on my side of town while I was sat still at a light or 4 way stop WITH paper plates still on them. Under 1k miles on them. I parked my 5.0 for the first month back in Jan for the three weeks I had paper plates. I even had the fiance drive it home from the dealer for me and park it LOL
You gotta love those deer Park girls... Texting and driving, make up and driving, if they made a plug in curling iron they would do that too.