There is a series of three videos on the net re: the Ithaca "Flues" model. The advice is NOT to shoot modern high pressure loads in them.
I have a nice "Flues" model with 30" barrels. I bought it for CAS but I consider it too nice a gun for that. I promised the seller that I would NOT butcher it by cutting down the barrels.
I checked the barrel flats and they are marked with what appears to be LLH on both barrels. What does that mean? The right barrel has the more open choke. Isn't that the opposite of what most SxS shotguns have? The bores do not seem to have been touched.
More recently I bought an Ithaca/SKB Model 100 SxS (F&M) off the EE. It has 28" barrels, extractors only. I'll use this in CAS and Trap, so the barrels will NOT be chopped. Always wanted a class SxS to shoot Trap with.