My old Model 1050 remote controlled my 27" Mitsubishi TV, so I suspect that the UEI database includes at least some Mitsubishi codes. This page offers four codes for Mitsubishi TV's: 0150, 0019, 0093, and 0178. I'd recommend trying those, as some or all of them should be in the 990 remote's database. I'd also try 0030 (listed under "MGA" in the Outlaw manual along with three of the above Mitsu codes).