I like the 465 but NEED overdrive and would rather have an automatic, so I am oppting for the 4L80 instead of the NV4500. I know the 465 is about 12" long while the 4L80 is about 24.5". I'm thinking I'll need to fabricate a new cross brace or just move the existing one back? Also I've got a NP205 on the back of the 465, would it need a new input shaft (its a 77')? Anyone done this swap, or with a TH400?