[GMC"ER]

Hello this is my first post and I am a newbie to the truck scene. I have restored a 1929 Model A Tudor sedan but now wanting to start on my truck. I have just bought a 69 GMC stepside that a friend started to do a amateur restoration job and lost interest so it is all stock but I want to drop it 2.5 in. in front and 4 in. in the rear and put rallies on it. I need to know if there is a kit form way of doing this? My truck has drum brakes and that is fine with me as I am use to that type of brake. I have researched on this website and read about the drop spindles, but the more I read the more confused I become. My truck is coil in front and leaf in rear drum all the way. I guess my question is can I lower my truck and still retain the drum breaks? Seems to me that once I start to change one thing I have to change other stuff and on and on...I am on a budget as seems we all are nowadays so can I just get some good advice I am just making a good driver something that i can go to local cruise ins that I can make better speeds than 40 mph as in the Model A. Can I just have a list of what I need to get to lower this truck as cheap as I can and safely as I can. I am just in the dark here! Also a few pictures of the truck and could not resist to show off the Tudor sorry for the wrong brand posted here! Thanks Robert