I've been playing clarinet for years and I really want to

Even if it's more different than you think, it'll still be pretty easy to get the hang of it I think

>>74284294
They're both in the same key and have relatively similar fingerings and shapes. And even the music written for them are very similar.
Source: classically trained in both

like >>74284445 said you'll be on solid ground I think because of the similarities, the only thing I can think of is that tenors obviously require more air, but I imagine that wouldn't be too hard to get used to

just switch to flute instead
skin flute

I play alto saxophone and I could switch to clarinet easily. You might have to blow a bit harder and build more embouchure for tenor sax but that's about it I think.