SM420 transmission

[Kansas Kid]

Ok guys, I need some info on this transmission.  About all I know is that it was used in most GM pickups up until the early 70's.  It was made by Muncie, and is a four speed manual transmission with a granny first gear.

 

So what kind of info can you guys tell me about it.  Is it a tough enough transmission to hold up behind a strong smallblock V8 or maybe even a bigblock?  I'm assuming it will bolt right up to most any GM motor.  What kind of gear ratios does it have?  I know that fourth gear is 1:1, but what about the others.  And finally, is there an adapter out there to allow me to bolt an NP205 transfer case behind it?

 

Thanks.