I'm sure some will say that your technique is bad, or you need to correct your playing position or something... but, I don't know.
Can't really comment about your particular basses, but I can tell you my experience...
I played a tele bass for a long time that has a big neck. 1.62" at the nut I think, but it's big front to back. Lot's of chunk - baseball bat.
Now I play a Jazz. 1.5" at the nut, but also is fairly thick.
I've never had any problem with either of those basses. The tele is obviously "harder" to play - but in the way that can make you approach your lines in a different way or whatever.
Now, I've had a few different P basses. Including a very nice AVRI 1962 P Bass. That bass in particular, but a few of the P Basses, caused me pain, exactly like you describe. Pain in my wrist, hand, and all the way down through my forearm. I sold that AVRI P, and a couple other P Basses because of this.
Maybe changing your bass height, or the angle of the neck, or your right hand position will fix the problem,,, but man, I just want to pick up a bass that I like, play it without thinking about it, and not feel any pain.
That AVRI P Bass has a wide nut -1.71" I think, but it also had a very "flat" neck. Very thin from front to back. - That's what I blame it on. Or maybe the way the body is shaped works into the way I position the bass,,, who knows.
What I've decided is that I'm not looking to rework my form or retrain myself,,, I'm looking for a bass that feels good in MY hands, the way they are. One reason I've committed to never buying a bass without playing it first.
I'm not gonna buy and play a Ric, just because. I'm going to play a Rick because I played it, and it feels great in my hands - and then after that, looks cool, and is a Rick, and sounds cool, and all the other stuff.
There is SO much variation in neck shape - even between the same models.