1MZFE, I have the same crusty looking oil hole (vs pie hole) on my 2003 Sienna.
I have had both the front and rear valve covers off.....replacing the valve cover gaskets, and spark plugs.
The valvetrain, front and rear, was just fine, no sludge.....VERY slight film that wiped right off.......thin tar film on inside of valve covers.....that I was able to clean off with Simple Green.
I had given it a double dose of AutoRX, though I do not expect to need to continue with that.....most likely was not even needed, but it was something I wanted to do to my "new to me" used vehicle at just under 90K miles.
I have posted pictures in another thread (motor internals).
As far as the TSB for avoiding damage to the baffel on the 1MZFE motor from narrow oil bottle necks and bulk fill tools, there is a "special tool" that can be bought.......
True to my BITOG loyalty, I just had to buy me a "special" oil funnel.
It is a ASM #OFTOY1001.
Required, NO, Nice to have yes......threads into the 1/4 turn oil cap threads, and you can set the oil bottle in it and walk away.....vs having to stand there and hold the bottle......as it will not stay there on it's own due to the shallow spacing between the "hole" neck and the baffel.
