5.3 bell housing patern

[425hp87chevy]

hello, I've searched and cant find what I'm looking for. i am considering swap my 85 k20 to a 5.3 and maybe adding a little boost. but not familiar at all with these newer engines. I'm wondering if the bell housing pattern matches the old pattern of the th350 n 400. just trying to figure what all I'm going to be getting into.

[Captkaos]

The trans will bolt up minus one bolt.  You need either a flywheel from a 1998 LS1 or an aftermarket one, and a converter for a LS1.  Adding an overdrive is better and the one behind the donor is ideal.  The NP241 off a 89-91 should bolt up and give you the correct side drop.