Gearbox ID and tags

[tonyabacus]

Found a gearbox whilst having a sort out which appears to be a 2000E, checked ratios by checking input/output number of turns. The ratios appear to be consistent with the semi close ratio set, with a input shaft diameter of 15mm.
There is a tag on the box which is very corroded and very difficult to read, but from what I have can anyone decode the tag please,

Top Line; 20?2 PEZ (the first four digits are barely readable as is the letter P, so these are as close as I can get)
Second Line: 7? E?23 (there may not be a number after 7 and E, the corrosion is to bad to see)

Thanks
Tony

[SENC]

I can't help with the tag (will go back and look for mine to see if it will give any clues), but there should be some date codes on the box and on the tailshaft housing that will help you id...