barrycarter, you are probably thinking of this strip, were Dilbert and an unnamed character are victims of AWS (attractive woman syndrome) : 1993-08-08
The Liz there appears to have been a bit part, rather than a continuing character, since her hairstyle was completely different, and Dilbert would not have a chance with her at all if they were the same character.
My dad is an engineer, and he has very good taste. He is also very intellegent and nice and friendly. Dilbert would have us believe all engineers are socially inept, stupid, and have bad taste, but they are not.
And nobody actually pulls up their shorts like that.