System tests referencing a second security

[HARELSDB@xxxxxxx]

I would like to reference a second security, such as an index, in a system
test and would appreciate any help the list has to offer.  The test I would
like to perform follows:

Buy ABC long when the x day moving average of the ratio of the close of ABC to
the close of index 1 crosses above the y day moving average of the ratio of
the close of ABC to the close of index 1.

A sell signal would be given by a cross of the x day average of the ratio of
the two securities below the y day average of the ratio of the two securities.

I can figure out how to write the Metastock code for this if I can figure out
how to get Metastock to recognize two securities in the same test.

Thanks for any help that is out there.

Dan
Pocatello, ID usa