NEW TO SITE! Engine swap questions

[PLYONS11]

Hi all,

I have recently acquired my late grandfathers 1963 GMC 3/4 ton long bed as a project. The truck has the original 305 V6 with 43k miles. Though this is cool engine, it isn't really practical for what I want (horsepower). The truck is 2wd and currently has 8 lug hubs. Plan to also do a disc brake conversion and swap out for 5 lug axels and spindles.

I know the answer is probably already out there in some thread, but I'm just not finding it. I would like to drop in a 383 or 496. I'd prefer a 496, but I find conflicting info on fitment. Is it possible to drop in a 496 without fabrication. I have little to no experience with fabrication, nor do I have the tools or space to do it. I can turn a wrench all day, but I'm not willing to attempt frame modification and can not afford to have it done. From what I understand a SBC will fit without any modification, but I really want a 496.

My plan is to keep it carborated or possibly using an EZ EFI or like product for fuel injection.

Any/all insight or suggestions would be appreciated. This is my first GM (don't hold it against me, I have multiple family members that work for Ford.)

I'm also open to suggestions on the trans to put behind either of these engines.