David- I just received a SFI rated steel bellhousing from "QuickTime". You don't need to do any modifications as with the Lakewood. I haven't installed it yet and I'll report when finished.
http://www.quicktimeinc.com/products.html
RM-6056 - FE Big Block Ford Bellhousing to Ford TKO 500-600/T5 Mustang/TR3550 transmission
RM-6056-SFI FORD 352/390/427/428 BB TO T5/TKO BELLHOUSING S F I 6 . 1 $ 565.73
Height = 7.050"
Trans. Bore Ø = Universal 4.850/4.910
Engine = Ford 352/390/427/428
Trans. = Universal Ford TKO 500-600/T5 Mustang/TR3550
Clutch Ø = 12"
Flywheel = 184 tooth
Weight = 22#
Universal shifter fork brackets for diaphragm or cable operated linkage
Has passed ALL SFI testing
Pivot ball, fork brackets, FULL engine plate and grade 8 bolts included.
FE TO TREMEC-