r6 clocks on '88 fzr750

[jiffy1986]

hi, im new to the site and own an '88 fzr750rt, got myself some 5eb r6 clocks and found the thread on here about fitting them to a 600. all the wiring on mine for the clocks is the same as the 600 (colours), but on the r6 clocks ive got no black (ground) wire. surely they must earth some way or they wouldnot work? any help is appreciated!