I too am guilty of removing the studs on the cam housings. In my experience some of the gasketing surfaces can be boogered up by somebody over the years. Also the gaskets leave some material stuck to the housing. Admittedy that gasket residue is not hard to clean off with a fresh sharp utility knife razor blade dragged across it perpendicularly (is that a word?).
Yes it's a bit of a hassle to take out all the studs. But it's the only way to get the valve cover surfaces nice and clean and flat. I figure if one goes through the trouble to surface the actual valve covers themselves, might as well complement that with the surfacing of the cam housing gasket surfaces? But I certainly admit it's not an absolute must to do this. I'm just OCD about certain things and I hate even weepy valve covers, on top of being somewhat of a clean freak when it comes to engine repair. I'm currently knee deep in the intake manifold R&R on my Corvette and the typical small block Chevy intake valley and the TPI runner connections on the manifold presents so many gasket surfaces (some of which have 30 year old metal reinforced gasket remnants that are unwilling to let go) it's kinda ridiculous.......
I also like to surface the sealing area for the heads and the camshaft thrust plate (the end of the housing) to clean up any crud and make it flat. You'd be surprised how NOT flat the surfaces are. Granted, I suspect the housing has a little bit of "twist" in it upon being removed from the heads and that's why the sealing surface isn't totally true. I color it with a marker and then run it on a piece of quartz countertop that has couple sheets of 400 grit wet sand paper taped to it, to see how flat the sealing surface appears. Honestly I think the most important thing making sure the surface is clean for new 574 orange goop application and that the cam spins freely in the housing when you torque it to the heads. Because it's got so many fastening points, I think it's hard for that surface to NOT mate up well with the heads.
Regarding the steel plugs. The only reason to remove them is if you suspect some crud is trapped around it. Even then, it's not hard to flush around them with some solvent and compressed air. But removing them is not hard at all. A few strikes with a hammer handle or something similar pops them out. Installation is just as easy. Put a swipe of 574 orange goo around the perimeter and uniformly tap it in place around the edges.
Here's some pics of the surfacing on the cam housing. Ignore the 1/8" NPT plug on the end of the housing. After doing that on a few housings, i'm not a big fan of it and would rather just reinstall new aluminum plugs.
