On my 86 Offshore I was able to access them all with the existing deck plates. I had some scrapped up arms and had to try bending them ways I didn't know my arms could bend but I got it done. I remember there were 3 in a close group on the offshore and it was easier to replace them all together. I just bought the PVC Perko ones again with the barbed ends, it looked like that what Grady used and then cut the barbs off some and put a 90 degree fitting on in some of the spots. The brass ones are defiantly a lot better, but the PVC fit the budget and they were all well above the water line and the old ones lasted 26 years.