SB to BB in '85 4x4

[NtheFamily]

I have a '85 4x4 with a 305 now and plan on building a '77 454 to put in it's place. Is there a past post that has a lot of info I will need to perform the swap? If not, is it a pretty easy swap? Will I need to swap motor mounts/perches? What style of HEADERS would fit? My truck has the heavy duty suspension, so will the front suspension be able to handle the BB? Will the 700R4 be able to handle the 454?

Thanks for all the info you can give me. I've swapped SBC's with SBC's, but never delt with BB's. I don't think I have nothing to loose swapping motors, but just wanted a little more umph when I need to pull something. I get 9 MPG now with the 305, which want pull a greasy spoon out of a cats a$$.