how to swap big block (454) in a 1961 chevy apache

[BruceTheTruckingCat]

HI there I have been thinking about get some power in my truck and with the 307 small block its not worth it to upgrade it. so im thinking get a 454 big block from the junkyard and swap it in. so i was wondering if anyone else has done something like this before. and if they could give me some about advice about doing something like this
I also have a few questions that if you could answer would help
1) How easy does it fit I have read some things that its a blot in and other people say you have to cut up the firewall.
2) for cooling I'm guessing that the 2 core radiator i have now will have to upgraded but i dont what to upgrade it to.
3) for transmission i was thinking a nv4500 would be a good pick. any thoughts on that.
4) if i get a 454 im guessing that its going to be from the 80's to the 90' so it going going to have bunch of emissions BS. So I think I would get a dual plane intake, a Holley 4 barrel, and a good pair of headers. Any thoughts on the HP