The Mellotron Group

hi folks...

i need a refresher course in replacing m400 tapes.
i'm doing this for a friend - mine are all in fine shape,
and i have not done this for about 15 years now.

so i have an old frame that needs its tapes replaced.
my understanding is that using the old tapes to pull through
the new tapes is a recommended method. [yes? no?]

i have a new set of streetly tapes [on the little red spools].
before i even break them out, i recall that there are marking
that pertain to:

1] cut here

2] start of sound [to be aligned with the heads once installed]

3?] are there key numbers on them?

so what do i need to do to use the old tapes to pull on the
new tapes. i remember when i did my last set i had 35 pieces of
tape hanging around my studio and tempting my cats to play.
sadly, i have no more cats at the moment, but i still think
that was not the simplest way to do it. i did some searching
around, but could not find a website with 'proper' instructions
on handling a fresh set of streetly tapes. these have been
sitting around for a couple years now and i weant to deliver
the freshly loaded rack to my friend kurt next week. i even
have an 'extra' m400 to use as a staging machine, so all i
need is the tutorial on this... and a translation on the marks.

thanks in advance folks!
jeff