Hi all....I'm new to the group and in need of some help. I have a Roland SolJet pro sc540 that appears to have three of the six heads misfiring. I've replaced the pumps, ink wells, and inks to the tune of about $2000 and still can't print a job. The Roland tech quoted me a price of $900ish per print head and that didn't cover the service charge! What I'm looking for is a service manual for the SolJet sc540 and the best place to buy replacement print heads. Also, has anyone out there ever changed the print heads? Thanks in advance....