13637 L34 M40 TK, Baltamore is the only plant to use a two letter designation, but after doing a search your drive line should be
"A '70 SS with L34, M40, April, Baltimore built car. Build sheet in box 19 says "TK". Nobody (here) seemed sure what the drive shafft colors should be. So...... I removed shaft and cleaned 40 years worth of grime off. Lo and behold I find (3) stripes !! From the front about 3/4 length back, Orange, Teal, and Black all in declining widths."
Some had a couple of extra stripes on them, not sure what plants
Hope this helps some.