I'd use the tardis first to go to all the many places I didn't get to in the late 50 s and early 60 s.
Then I would go to the WCML, around Golborne, and watch the endless procession, most of them hammering down the fast straights.
Another area a little further north, was Taylors lane bridge overlooking the branch, and the sand brew, where you could cover both Wigan NW, and Wigan Wallgate.
mickey
