67 SWB Upgrade Questions

[K5_Knox]

I don't mean to beat a dead horse here, but I have read many mixed reviews on swapping from 6 lug to 5 lug. I'm looking for the easiest economical way to do the swap while upgrading to front disc brakes and a better suspension.

Vehicle is a 1967 GMC SWB.

Also, I can't figure out how to decode this SPID. Seems as though the fourth digit means panel, what am I missing?

Cs1570d pc1059ca
dd

C=4x2
S= 6 cyl
1=half ton
5=???
7=1967
0=???
D=???


BTW, I'm relatively new here and am amazed by all of the knowledge, hospitality, and ease of use that this site offers! Only issue is that my wife thinks I'm having an online affair because I'm always reading the build threads and constantly searching for parts!