If I replaced with a alternative material to the
"planks" I would construct it in the the same manner i.e. with the split as I am aware that it can not be removed in one piece once the springs are bolted in place.
TBM has a valid point which I had not considered regarding exposing the drain plug when using a thinner material but is not insurmountable. Like him I will be moving the tank rearwards due to replacing five leaf springs with four leaf springs. (As in my previous post).
TBM is your tank sat flat on the boards or is it sat on spacers so that there is a space beneath it?
