If anyone is in David Harrison's 'L' / CHICAGO ELEVATED FB group, he posted a nice b/w video of the northside L in the 70s. Starting at the 2:50 mark, there is a clip of a combined 6000s/5-50s train going over the MILW ROW on the Ravenswood. There are additional clips of the MILW crossing at Addison and Buena yard.
https://www.facebook.com/groups/3027704194214804 Cheers,
Mike
