Slug Gun barrel ODs and frames

[whiffelball]

I have questions about barrel diameters and frames since I'm making/having made custom stocks and open sights.

I am looking at rifled slug guns.  I have read that 12ga USH barrels are made on a 10ga frame [SB2] and using a barrel large enough for the 10 ga, but only bored out to a 12ga, thus the heavier barrel.  The 12ga is on the SB1 frame, and presumably uses a 12ga blank bored out only to a 20ga.  Make sense, but...

QUESTION 1: HR1871.com says that the weight of these guns is either 8 or 9 lbs.  Which is which?
QUESTION 2: What is the Outside Diameter of the 12 and 20ga USH barrels, respectively?
QUESTION 3: Do the Tracker II and ULSH have the exact same barrel contour? 
QUESTION 4: What is the muzzle Outside Diameter for the Tracker II and ULSH?

[Lon371]

 20 Ultra slug is 1.11 at the breach
                        .97 at the muzzle

 And ways 200 pounds if you carry it all day

12 gage ultra slug is on the 10 gage frame, sb2 I believe

Lonny