Contact Steve as he will have valuable input to finding out what is going on. BTDT and the knowledge that he contributes is priceless.
As for the smoking your valve guides are very likely worn. If you removed the cat for the pre-muffler you will see the smoke that the cat burned up. I rebuilt my engine at 88,000 due to two broken head studs and worn valve guides. Mine didn't show any smoke until the cat was taken off. Beware of the "while you are in there addiction"
