Ted is the resident expert in French guns, perhaps he knows how the I beam ribs were fitted before soldering atthe factory.

I have seen the "I" ribs off the guns during repairs. The barrels grip the "I" beam rib pretty firmly along the whole length and need light clamping only at the muzzles during soldering. The process looked much easier and was faster than that used in two rib relaying.

The ribs I saw being relaid were all swamped ribs sitting pretty low between the barrels. I do not know if Manufrance made "I" ribs in any other shape other than swamped for the Ideal.