I have two matser cylinders. My 08E car had when I got it a 309 dated 143. My 12A car has a 346 dated 52. Can someone decode these dates. Also on the site I have read that early 69,s may have left over 346,s on them. Does that mean my 346 could be original? And my 309 US appears to be original but the date does get close to the date on the original trans. Would they have built many and used them later as it appears they did on the 346,s?