904 torqueflite identification PLEASE ???

Not sure exactly when 904 transmissions went to a lock-up torque converter, may have been in 1978 or a little later. You can't swap converters between the older, "regular" ones and the lock-up versions. You can spot a lock-up transmission by a machined shaft at the tip. The splines do not go all the way to the end on a lock-up style transmission. Not sure how to I.D. a lock-up converter.

Be careful with OEM bands and clutches. 904s hold up very well with the right mods. There are "red" bands and/or clutches that are the favored versions, but I forgot the brand name. I don't get into them myself. A trans cooler is always a good idea, a deep pan & p/u and a 3.8 or 4.2 kickdown lever would be better than a smaller #/ratio. You can also get a 2.71 low gear from a later lock-up 904. Most, but not all, lock-up 904 will have a 2.71. But there is a certain combination of parts and clearances checked when swapping over.