I just acquired a D5 xl dichroic (from another APUGER). Great! There's a 6x7 mixing chamber (D-B) available, but I want to be sure that the one in the head I have is the 4X5 (D-D). I can see that the top of the lamphouse opens up, but is there an easy way to get to the mixing chamber? I don't have a manual yet, and this opportunity (auction) is passing this evening! Of course, if the bidding doesn't go too high, I''l buy it on spec ... Thanks for any help! David PS: Anybody have a mounting collar for the column? This machine came sans baseboard.