I think its very likely that Markham already has the dimensions of your NH bucket. I'd give them a set of measurements, but the way the toothbar is made, the side hole is a slot cut out of the toothbar support. When you put the toothbar on, you bolt through the slot and it holds everything very snugly in place. Mine has never moved in over a year of very hard digging. It could only move when I am backdragging anyhow.
So I'd say that Markham will probably have your dimension already when you tell them the bucket brand and size, but take some measurements and have them ready just in case. I bet you'll get a toothbar with slots. Mine from my NH dealer did and it looks just like the Markham bars. /forums/images/graemlins/cool.gif