Need help identifying year of my suspension

[TexasSixtyFourSW]

Hi Everyone,
I have been lurking for quite a while trying to get my project off the ground. Long story short--I first bought a 64 BBW Short Fleet that is a huge project and decided to find something running and driving. I found a 63 BBW Short Fleet and I am going to use all my parts on the 63. The 64 I bought has been converted to 5 lug and I would like to use that suspension on the 63. I don't plan on doing the suspension swap for a while and would like to lower the 63 as much as I can ( Six Lug right now) using coils. I realize the spindles are not intrchangeable between the stock 63 and newer suspension but if I buy coils to drop the 63 can I use the same coils on the new suspension? I will buy dropped spindles for the 5 lug suspension after the swap more than likely. If anyone wants to share their ideas or thoughts it would be greatly appreciated. I also wonder if anyone can tell by the pics what year my suspension parts on the 64 are?