Smoking 273, opinions?

My 273 is smoking fairly good out of the left bank when I'm on it over half throttle or more and above 3k RPM. Compression tested all cylinders and all were 105-110, but the plugs on 6 and 8 are oily. I replaced intake valve stem seals with new felpro seals on 6 and 8 and plugs are still oily after a new set and it still smokes. I was lazy and only changed the intakes on 6 and 8 instead of every seal on every valve, mostly because I've been limited on time to wrench on it.

I have NOT done a leakdown on it yet. Starting to think the rings have gone to **** on 6 and 8 and that is my problem. Any thoughts?

Engine is stock bottom end, hydraulic flat tappet comp cam 279/296 .486/.473, stock 318 heads, Eddy performer intake and 600cfm carb.

Gracias Gents!!!