Depends on where you are getting the update from.
On Landracing.com main page are the confirmed rule changes right on the front page - As for the MS section you stated upon.
"5.D.4 Modified Sports - /BFMS, /FMS, /BGMS, GMS
Streamlining ahead of and including the cowl, channeling, belly pan and skirts is allowed. Front tread width may be narrowed to a minimum of 27 in. Removal of minor trim and bumpers is allowed as long as the body is not altered in length, width or contour. Spoilers as defined in Section 4.CC.6 are allowed. Windshields may be lowered or removed. Coupe tops may be chopped. "
As of Today December 21st : The rules on the SCTA website are the PRE-BOARD approved changes.. Which means that is what went in front of the board. The actuall approved changes are posted on Landracing.com.
I got a copy of the approved changes Dec 10, 2007 and were promptly posted to Landracing.com.
But I guess when in doubt and I quote from Speedweek, "The SCTA-BNI website is the most accurate and up to date information", I guess you could email someone there and get an "Official" answer, or Dan frequents the boards and is a huge asset to this website, maybe he will comment on the correct rule
Jon