3/4 to 4/6 -- A little advice, please (1,001 times this has been asked)

[Captain Knievel]

Hello suspension experts. Nothing's easy for me, but this should be for you. I've been searching and reading the board for a few hours. Just need a little to make sure I know what I need before grabbing for my wallet.

The truck: '70 1/2 ton LWB, 6x5.5 ralleys, drum brakes
Current setup: 3/4, coils only, lowering shocks all around (not relocated in the rear)
What I want: 4/6

What I think I need after studying this a bit:

• 2.5" drop spindles for the front
• Remove the 3" coils and replace them with my stock ones, cut to get 1.5"
• 2" rear lowering blocks to go with my 4-inch coils
• Bolt-in C-notch for the rear

But, here's where I get all wonky:

• For the front: Since I have drums, do they make a drop spindle for the front if I want to keep my drums? Or do I need to go the disc brake route? If I go the disc brake route, am I looking at also having to go 5-lug?
• For the back: Do I need the c-notch if this is not a daily driver, I don't haul anything in it, etc.?

Thanks for any and all help.