300mw small brass red laser housings

If I were to order on Ebay some 5mw red mini brass laser modules that are factory sealed and house 5.6mm diodes, then could it be possible to "grind" open the back of the module and pull out the existing diode and clean up the module inside and replace the diode with a 20x long open can diode and use a "driver outside of it to get a small beam that is HOT!