Just wanted to toss my thoughts in. I have an 02 tb ltz with 168k on it now, and I seafoamed it right after I bought it at 167k, it did smoke quite a bit, but cleared up in a few minutes, I did get a cel from the o2 sensor. But cleared that using my bluetooth adapter and torque, it hasn't returned and has passed emissions twice, with lower readings after it. I haven't had any problems with the cat, and I believe it is still the oem one.
My 07 was also seafoamed at 66k, didn't smoke at all, and no cel. It's at almost 79k with no problems.
As for the vacuum line, I used that method on both, I did quite a bit of reading on it, and I remember that on some cars the brake vacuum line didn't reach all cylinders, but on the I6, it would. If you did use the spray, it wouldn't be the same as the brake line, since that is putting it in the crankcase, instead of going past the intake and burning in the combustion chambers, then out the tail. With the brake line, it would go throughout the crankcase, then with the lack of a pcv, back into the intake, and then burned, doing a better job of cleaning. Could do both if you really wanted everything clean.