the 3 in of water doesnt concern me
I would check the motor real good
remove the plugs and put a bar on the crank pulley and turn the motor over
If it turns 360 motor is prob good
If she binds or sticks - motor sucked up water and bent a rod - let her fly
6500 is a little high
keys?
will the dash come up?
jump it and try to turn it over - check that motor.
Try to get it to turn over at the min.
Ask good questions.

 

Had an 95 Imapla get about 2 inchs in the car.....Never Could get it to run right after that Filed it with State Farm.....They Rebult the Hole bottem Of the Car at a Dealer...Had phantom
Problems with the Car for Six months...As much as i loved that Car it had to go and i lost alot but i got out of Probley a bigger loss of trying to rebuild the hole damn car..
Unless you are going to Gut this car down to the Frame and start all over...Spend your money some were else....