Holding Tank
The original holding tank in my '86 Cal33 was the bladder type and was simple enough to remove. The trick was getting a rigid one into the same space through the opening in the V-berth but I did find one that just barely fit. It's only a 13 gallon tank and we haven't had a problem with that size yet and I installed it four years ago. If I had it all to do over again, I'd do a few things differently. Check with the Head Mistress before you go too far, that's no.1 on the list. I think I'd get a bigger tank and cut the V-berth opening to get it in but I'd look into a tank that has the discharge pipe come through the top instead of the bottom like most tanks do. I know someone makes one like this.Your original tank may not be the bladder type since your boat is a few years younger than mine but the end result may be the same, open up the hole in the V-berth. I think I'd add a significant stiffener across the top of the tank after you install the new one though just so you don't weaken that area with the larger opening. Perhaps save the part you cut out, then re-install it with an aluminum flange all the way around it. Just a few thoughts.Best of Luck,Chuck