I just finished my first DC Commander Upgrade and it was easy. A couple of years ago I purchased a K-line F-7 A unit that was a slave with the intent of adding TMCC to it. About a year ago I purchased the upgrade and looked through it and felt a little intimidated by it. Well tonight I finally got the nerve to try installing it and it was simple, took less than an hour. The only issue I had was I couldn't figure out how to replace the front coupler with a new coil coupler. That is for another day. For now I've added another engine to my growing roster. Next I think I'll do the same thing to a Williams BL-2 I just purchased and this time add railsounds.
James