First Butt questions.

no, definitely not to early, in fact it is recommended. if you want more smokey flavor then add more chunks. you can also mix some small chunks in with your coals in your basket, that way you dont have to add along the way, there bye not needing to open anything to let out heat, smoke, or humidity.

I know everyone has their preferrence, but I prep & rub 24 hours before, wrap in plastic, and refrigerate.

When I use my WSM, I start off w/ 5 chunks the size of my fist & dont add any more during the smoking process.

...just the way I do it

Mix your chunks in with the coal and leave the lid closed. Have fun!

IMHO the longer you have to season/marinate your butt the better it will taste. What are you seasoning with? Just from my limited experience, you should inject before you rub and when rubbing, don't actually "massage/rub" the meat, just coat without rubbing in. You want the smoke to penetrate the meat and when you rub you basically form a closed seal over the meat.

I don't rub until right before it goes on, and my pork has been judged as pretty good. I don't think pre-rubbing does anything but make a mess and waste rub, all your getting in juice after the rest (more than a few minutes) is water anyway. Why waste rub?

I've done a butt or two (thousand) over the years. Unless your rub is rather salty, and unless you really like very salty pork, I haven't noticed much of a difference in rubbing the night before, 24 hours before, or whatever. Now I pretty much get up at the crack of dawn, inject and rub, then go light the fire. Like Pimp said above, you're pretty much wasting the rub. To test this (I have), rub one butt 24 hours before, rub the other 1 hour before. Cook them side by side. I'll bet you can't tell the difference. For fun, do 4 butts, and then foil 2 of them (one rubbed early, the other late) at the 4.5 hour mark. See if you can tell the different then. We can, but only in the foiled vs. unfoiled. This is why we foil.

I won't give it away, but I bet the butt you rub 24 hours ahead tastes like a traditional easter meat. If a salty. phosphate rub.

LOL. Yep, been there, done that, gave it all to a friend of mine who like a little food with his salt. But then, there are folks who like very salty foods... To each their own.

If ya go PimpSmoke's route I don't think you could be disappointed. I tried rub just before chucking pork to smoke and it was great. Good bark, great flavor, no soggy mess on my meat.