I have a CPE2 and would like to try it with 4x5" film. The drum that I have is a 2820 test drum. I understand that I need a 2521 drum and a 2509N film reel. My questions: Do I also need a 2508 loader base and a 2512 loader guide? And will they make loading real easy? I have read previous posts about people having problems with uneven development with the 2509, is that fixed with the 2509N? Please feel free to comment and add your experience with the CPE2 + 2509N!