1968 Sub vs Sub tips?

[Skyhigh]

I made a challenging '68 boomer hunting mission:
1-3 Yankees escorted by 2-5 attack subs: Foxtrot, Whiskey, Tango, Romeo or November. Sometimes I have a Victor I in there but that raises difficulty level a bit.
Goal is of course to take the boomers down.

Now of course the Mk37s are pretty slow and the escorts easily outrun them. How close do I need to be to get a hit with a Mk37?

Right now I actually use the Mk37s to chase escorts away (if far enough away, they will just turn their tail and run off) and then try and get close to a Yankee by speeding up into its baffles.

However it is not always easy, as it is unclear how many escorts there will be.

I have yet to kill a Yankee, because this mission is pretty difficult.