[dangerous]

if you replaced your upper radiator hose and it's leaking, you might want to determine exactly where and why, then fix it. It's not an SR-71 so leaking is not normal and acceptable.

Leaking in the area where your water pump and oil cooler meet is is more likely coming from your water pump. The oil cooler housing CAN leak coolant in this area too but it is less common. The more common leak in the oil cooler is the internal seal that allows oil and coolant to mix. The common symptom being a milk shake looking mixture in coolant and/or oil.

I'd suggest you drain your oil into a reasonably clean pan and funnel it into a glass or plastic containers that are transparent or translucent. And empty gallon jug from distilled water for example. If you have coolant leaks you should have a couple of those laying around. This way you can see if there's water in your oil (it'll settle at the bottom). If you have water in your oil you know you need to replace an oil cooler seal. Note: this as nothing to do with the coolant leak you were describing but since you described oil pressure concerns it is a good first step on that investigation.

Oil pressure sensors can get a little wonky sometimes with age but more frequently you'll see oil pressure relief valves sticking if the oil gets dirty and gummed up. This is why I would recommend that you pull the oil cooler and replace those seals even if you don't find water in your oil (or oil in your water). It is a common problem and the seal kit is cheap. You're going to be digging in just around the corner anyway so do yourself a favor and eliminate it from your future to do list now.

I've done oil cooler seals with the exhaust manifold in place but it is so much easier to remove it. I use a mixture of acetone & ATF as a penetrating oil and have found nothing better for rusty exhaust system hardware. Take your time treating those rusty nuts and studs because drilling out snapped off studs in an aluminum head is much less fun (ask me how I know).

I like to run a thread die over engine studs for the exhaust manifold AND the water pump before reinstalling those parts. Cleaning up the threads doesn't take much effort but makes things go back together easier. Those water pump studs are small and it doesn't take a whole lot of corrosion to weaken those too. Use the acetone/ATF mix on those studs too if the look cruddy when you get ready to remove that water pump.

There's a cork seal on the cam tower rear cam that frequently leaks and drips oil if that's where you're seeing leaking oil dripping on the manifold. Otherwiise just replace the can housing gaskets when you're doing your front end service, since your timing belt is already removed. Not expensive or difficult. Just be careful not to drop your lifters out of the cam housing when you lift it off. Rotate it toward the.exhaust side when you lift it and this should help keep them in place.