Generally, yes. Many builders on the FFR forums mention this. Seems to hold with 302/351 and Coyotes. The recommendation is often to cut the bottom of the bellhousing to match the bottom of the 4" frame rails. There are also many warnings about having an
oil pan sit below the frame rails.
Having had two SPF cars I was accustomed to the front sway bar being the low point under the frame at the front and used that as a guide for what hung down. In 65,000 miles never hit the bellhousing or
oil pan. This was with a 3-1/2" or so height to both and driving cross country, city, country and dirt roads. YMMV
The standard recommendation for chassis height on the FFR at the bottom of the 4" frame tubes is 4" at the front and 4-1/2" in the rear. This is an approximate and often varied from. The SPF chassis used similar heights.
I understand the concern but wonder if this merits the effort.
Jim