This is on my 76, dont know if this is usefull to u or not, but.
Yes u can. DIY4x brackets, depending on which side u put them will determine the use of 52 or 56. Just make sure u bolt the springs on with the long side to the rear. Unless u want to move ur axle back, or put one each way and mount ur axle in cocked and run down the road with the truck sideways a few inches.
I just installed mine a couple weeks ago, havent drove on them yet.
Brackets from DIY
I made the shackles out of 3/8, they are 1/2-3/4" longer then stock, dont remember exactly. Reason I made them, the bolts are 9/16, I dont want sloppy holes, so I drilled them 9/16". The shackles u buy will have bigger holes for ease of installation, that will also allow the sleeve to sometimes slip into this hole partially. I wanted good sleeve contact on the shackle. Also the shackles u buy will not extend all the way to the edge of the bushing, I also wanted that(see last pic), dont want the shackle trying to cut into the side of the bushing.
Greasable bolts and DOM sleeves from offroaddesign, also installed a zerk in the flip bracket, also replaced the sleeve that came with the DIY bracket with a DOM sleeve.
This pic (cellphone), everything installed. no load on springs, shackles are almost straight. U dont want them perfectly straight, cause u dont want them trying to flip the wrong way if a wheel comes off the ground. Granted in this pic the axle is not on, but I did stand on each spring simulate the weight of axle and tire, there was almost no more droop caused by me standing on the spring.
Weight on the springs now.
After I got axle and wheels on I jacked up on one side of the axle to check shackle swing.
U dont want ur shackle swung to far back when truck is on level groud, if it is it will limit spring flex, I have seen pics of shackles almost stright back when longer springs were put on with out the correct brackets, that aint good.