wrench 87 goto threaded plugs except for the back cam plug, Make sure this one goes in with the convex out and use RTV sealer so it doesn't leak. Use NPT plugs, drill and tap, make sure you clean out the motor before you assembly. I think there is more plugs than 6 for the oiling system, this depends on the motor. There are 4 that flank the cam bore, 2 in front of the block, 4 in back of the block. Make sure that you don't put them in too deep and restrict the
oil flow. 1/8" or 1/4" NPT plugs are used, add a light coat of pipe dope to the threads of the plugs. Make sure area is clean. REMOVE and extra. There is an article about FE oiling system up grades. Put limiter in your
oil feeds to the heads, depending on which rockers you use, from .070-.090 oriface will give plenty of
oil and keep most in the lower end where needed most. Rick L.