Ampeg V4.com

So I bought a set of matched quad TAD 6l6GC STR's and installed them. Shoul be plug and play right? No biasing needed right. But here are some dumb questions maybe. Since they were bought as a matched set, I installed them how they were shipped, taped together in a row of 4. All the numbers on the stickers are the same except for one of the specs... In order of tubes 1-4 here they are a57, c27, b02, and a66. What do these mean? Also another issue is their overall sizes. Tubes 1&3 are taller than 2&4. Does that mean anything? It's only a few mm taller but has me thinking these aren't really matched or there are some quality control issues. Am I overthinking this? Thanks guys, I just don't want to damage my lovely amp