For the front, if you don't want to drill out the lower mounting point , it's a bit pricey...BUT YOU WILL NOT FIND A BETTER SOULTION
http://www.x2industries.com/control-arms-dodge-c-89_568_579_615.html

the 94+ front drop springs work for about 2-3 inch drop, on your 79 it will be a 3 inch drop, but I've had alignment issues with those springs, , not enough camber on 3 of the 5 trucks I've used them on....Quality control on these 72 -80 trucks lacks a bit. I used a modified B- body upper to fix it.

for the back since you want to be able to go back to stock if need be, just flip the axle on top of the springs, no need to c Notch unless you plan on carrying 750lbs or more. I've found thru the years that a W300/350 rear springs work nicely with a axle flip, gives a about a 1-2 inch arch, remove some of the spring pack if it's too rough of a ride.
one suggestion that will be hard to return to stock.....move the top of the shocks as close to perpendicular as possible(or bring the top as close to the frame rail as you can) ride quality and traction increases by a fun factor of AWESOME.