JOHNSTON 135 HP 1975<br />I what to re-install my existing water pressure gauge to this motor and also a pee hole.Have looked at many posts,but are not 100%<br />sure on the point to tap it.On no 1 side of the block their is two prongs in line - above top one ,there is a<br />small flat spot, that looks like a little circle.<br />this is where i think you tap looking at other posts.<br />Thankyou in advance for your help