Send it over and I'll try some of my Husky flip caps to let you know. Probably need a few years of testing to say for sure though.
But seriously, I'll try to remember to put calipers on them and compare to the older saws I have next time I'm at the shop (next few days are not promising for that!). Do you know if the 346XP caps are interchangeable with other saws? maybe something like the 338XPT that probably overlaps manufacture date would be similar...but that may be smaller? Perhaps my 455 Rancher (also may be same vintage) or543XP (newer)?. The only Husqvarna I have with flip caps is a 562XP I'll see if those caps fit any of the others.