Re: \'83 K5 trans swap
Yes, it is quite extensive. I swapped the 700r4 and xfer in my 86 pickup to a 465/205. The years are a little off, but the parts are the same.
Since there was only one year (74) when the 203 came behind the 465, you'll most likely have to swap the xfer too. What I can think of off the top of my head:
Move crossmember (drilling holes, etc).
Lift that heavy A$$ POS up into place.
Change driveshaft ends and lenghts.
add petal cluster with clutch
drill hole for linkage to run down through
Add pivot bar w/ additional linkage to frame/bellhousing.
Change flex plate to flywheel
add pilot bushing to end of crank.
cut hole in floor for shifter(s).
I'm sure I've missed something. At the time, I remember telling myself that I'd never do it again. But now that it's been doen for a while, I'd probably do it. You can't really get into much trouble, providing you have the right tools and ability. All you have to do is ask questions here and we'll help you get through it.