Right then! I managed to get some time back in the garage last week cleaning up my OEM aluminium cam covers in preparation to bolt back on thus sealing the top end, however, it didn't quite pan out. The cam covers were shot blasted and cleaned ready to refit but during the installation of the baffle plate spacer bolts I had some issues. I screwed in all the spacer bolts in by a thread or two then started tightening them in using a 1/2" ratchet fitted with a reducer allowing me to use a 1/4" drive socket, however, during this process the bolt sheared and I inadvertently clouted myself in the top lip with the ratchet handle
Following that little set back I tried another and sheared that also, after further investigation it appears that the root cause was that the oil had varnished with in the tapped holes making the bolt tighter and tighter as it was being screwed in and eventually the bolts exceeded their tensile strength limit prior to bottoming out
By reusing the OEM covers and sealing them with Wurth Super RTV I thought I would save some money to put towards other bits I still need to get but in the end after some reading on this forum regarding the JP4 plastic covers that have a replaceable rubber seal and making them easily removable if required I have finally gave in and bought what appeared to be the only cam cover assembly including OEM breather system on eBay at the time for £45 (bargain)
The cam cover arrived yesterday so from the info dotted around the forum it appears that no mods are required and they just fit straight on, during the installation I did notice that in one of the aluminium cam covers there is an o-ring type of seal that locates into a hole in the baffle plate and then into the cam ladder allowing the crank case to breathe but during the JP4 cover installation I did notice that there are 4 long slots cut into the plastic baffle plate (1 either end of the cam covers) the only possible issue is that the one of the slots in the JP4 covers doesn't line up the what appears to be the crank case breather hole that would normally have the o-ring seal fitted.
Not sure if anyone that has converted from the aluminium to JP4 cam covers can remember if the slot required modifying allowing the breather hole in the cam ladder to fully line up and allow the crank case to breathe correctly without restriction and potentially causing back pressure in the sump.
The red arrow on the photo shows the crank case breather route and the yellow lines show the misalignment between the crank case breather hole in the ladder and the breather opening in the JP4 cam cover.
Hopefully this makes sense.