I mounted my guage at the rear of the push cylinder in a tee. I'm only interested in 'push' preassure. My guage is replaced by a plug for normal operation and it is used on other hydraulic equipment that are fitted with such a tee and plug. Once installed on the splitter I may leave it in place for a few days but then it goes on a shelf in the shop.
My most common use for my pressure gage is to adjust the feed wheel pressure on my chipper.
On the splitter it is fun watching the gage Vs. ram speed as the two speed pump cycles in and out. Only the toughest wood kicks the pump into low speed. My pump in the 28gpm Barnes direct coupled to an 18hp Briggs IC and a 5" diameter cylinder.