Lockup Transmission Conversion
904s, even HD ones, are not that hard to come by- the conversion can be done, but why go through all the cost and hassle of converting?
If you were closer, I'd trade you for a non-lockup. The lockups are getting hard to find around here.
However, if you insist on this, this thread is a good primer for what you're in store for, and what the differences are.
How to identify a non lockup A999 transmission with pics!