One tiny crossover fic is all I have for the original PR series (with the exception of some Building Family fics that are set during Ninja Storm and feature Trini).

Shuttle Troubles: Liam gets tossed into yet another dimension and gets to meet five very unusual teenagers.
Complete / Standalone / Gen / Warnings: None / Crossover (Mighty Morphin' Power Rangers) / Note: 2nd season
Characters/Pairings: Liam Kincaid, Zordon, Alpha-5, Tommy Oliver, Jason Scott, Kimberly Hart, Billy Cranston, Zack Taylor, Trini Kwan
Words: 4525

Power Rangers fics
Fandoms page