Arrrgh....

Double check your grounds...
Where do you have your battery ground attached to the block and the body,I hope....
Had a Hot-Rod that would fire when I let go of the key because the starter was using all available power and ground due to a bad ground strap motor to body.
You can not over ground it....
Just a shot in the dark.
Hope it starts and runs soon ,can not wait to see it broke in and spinning that turbo.
TXDart