1966 Chevelle LS3 engine swap with 5L40-E automatic transmission

[bhsanchez72]

I have a 1966 chevelle and I am planning on doing an LS 3 engine swap with a new transmission. I am planing on putting a 5 speed 5L40-E automatic or a 6 speed 6L80-E automatic transmission. My question is, is there any way of knowing or does anyone know if when putting the new transmission in the bell housing of the transmission will fit in original tunnel part of the floor or will it need to be cut? Thank you for your help!

[Pete68]

The 6L is a big trans, its tall, u have to cut everything up. I want to do it to but im debating if worth it. 5L is maybe front drive cars only?