Yes, I've done it on the 945 and the 245 with no trouble. The 945 was done early on, one of the first reasonably involved bits of maintenance I tackled on the car. Awkward, but not hard. Took me 2 hours, being careful and not removing the intake b/c I was nervous about getting in too deep.

Make sure you have a new o-ring for in between the box and the block (and make sure the old one is accounted for and removed--it was stuck fast to the block on one of my cars).

This is much less tedious if you take the intake manifold off, so it is not a bad idea to have a new intake gasket on hand. Heck, be real thorough and plan on cleaning the throttle and replacing the throttle gasket while you're there. Just have a magnet on hand to retrieve the intake nut you will drop into a dark crevice while trying to thread them back onto the studs during reinstallation.

It is true you don't want to mess with the front drain tube under the box, but I can't imagine how you'd disturb it accidentally. From my experiences with this, it would take some intentional and vigorous poking and prodding at the tube to create a problem.

There have been numerous reports here that the aftermarket box from FCP is crap. The 945 has that box, no problems after 1 year and 12k. The 245 got an OE box from Tasca, FWIW.

John