Seeking Blueprints for 1971 Superbug chassis

A customer brought a bare '71 VW "superbug" pan, wheels etc, and 4-speed
into the shop (no motor, no body etc), and wants the pan detailed so he
can bolt his own stuff on top of it. He's willing to pay for a week of my
time to go out there with a tape measure and calipers and stuff and
actually characterize the thing, but it occurred to me - there _must_ be a
blueprint of the significant dimensions somewhere - didn't they make
millions of them? I'd be happy to charge this guy for a week's worth of
NRE, but I'd feel like I was ripping the guy off, if he could just get one
from VW itself or something for a lot less money than it would cost him to
have me draw it.

Of course, the PHB is way happy that the customer accepted my estimate;
it's not an insignificant amount of money, and he told me to go ahead
and search out a print, and we can just bill the customer for what time
it takes me to find an existing one.

Hope that makes sense.

Also, I apologize in advance if this is an inappropriate crosspost -
I went and looked at r.a.vw, and there's nothing but old spams, so I
thought I'd shotgun it. If you do have an answer, I'd appreciate
at least one crosspost (so I'll catch it), maybe with your followups set
to your "home" group. :-)

Thanks,
Rich