Brake Parts ID - need help identifying

I bought a set of 10" front drum brakes for my '68 Barracuda to upgrade from 9", but I'm having difficulty verifying the parts are all matching and need to order brake kits and bearings. Wondering if anybody knows what the casting numbers on these parts correspond to and if they're all compatible...

So, I'm throwing my coin in the fountain-of-knowledge and hoping for a miracle ;)
Here's what I have...

• Brake Backing Plates: both read 606 / L8
• Spindles: both have 3402738 with one ending in 191 and the other 188
• Hubs: one reads KH9, with the other H91042. In both cases, numbers are obscured by the studs. Both hubs are SBP hubs.
• Brake Pads: as installed measure 2.5" in width
• Wheel Cylinders: one read 3699927 / T12 & 3699926 / T15

That's all I know - hopefully, someone can fill in the details.

Thanks in advance!
-Chris