i also bought the 1" plates to get my motor far back as i wanted. my truck came with a 305/th400 combo. i didnt mind moving the crossmember back. the fitment to me is better than factory. im using a 60e tranny, i had to drill 2 holes to move it back.
correction i remember i drilled and tapped the adapter plates to set the motor furter back, so the motor is sitting back more than 1".