Misc. Questions on new 1963 Pick up. Engine/Trans.

[1Loud63PU]

Hi everyone, I am new to the forum.
I have a 1963 pick up with a 78 drivetrain and suspension, I may be posting in the wrong section of the forum since I have a 78 drivetrain, sorry if I am.

I got this truck about a week ago, I believe it has a 450 v8 engine.
I just ordered some summit racing headers for it. I was thinking of getting 2 flow master mufflers, super 10 race muffler.
Any thoughts?

I will be cleaning the carb next weekend.
It has a Rochester quadrajet-17080230----0290CMN

The truck will start right up with 5 pumps of the gas pedal. It has some back firing during take off at red lights or stop signs.
I am thinking it needs a carb cleaning and rebuild.

Looking at carb kits, found a few on ebay, 1 on carbs unlimited and 1 on the carb doctor.

Best recommendation on where to order one that will come with everything needed for the carb?

It has a light transmission fluid leak too that has to be addressed too.

Pretty much it for now.

Thank you in advance for any help.