I've been working on some chili peppers and hendrix songs lately (under the bridge, axis etc etc) and I'm having a hard time making some of the transitions between chords.

I've been used to playing nothing but power chords but have been practising holding the chords with my index finger on the high e and thumb over the neck on the low e (watching youtube etc it seems like this is the preferred position to free up the rest of my fingers for hammer ons etc)... The biggest issue I have is that my hands are pretty thick, when i'm playing a song like 'under the bridge' etc I find that my palm mutes the high e at times when i'm trying to pull my thumb over the low e.

Are there any exersizes or alternate ways of forming the chords that could be suggested to help get a bit more comfortable with this stuff?

thanks a lot!

I don't understand, I can't picture what you're doing. Post a tab of the chords you are trying to play, with the fingers you are using to play them.
My name is Andy
Quote by MudMartin
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Swinging to the rhythm of the New World Order,
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Just do the barre chords normally, the hammerons and pulloffs can still be performed. It'll give you a much cleaner sound.
a picture would be nice... in general its best to keep the thumb behind the neck for playing chords/ doing stretches and the theumb is brought over the neck to bend strings.
Actually, you can't really play some of that Hendrix stuff without using the thumb
for the low E. So, if you want to play that, you pretty much have to do it that way.

You probably need to experiment adjusting your hand position and arching your
fingers so your palm doesn't touch the high E. A large hand is actually an advantage
for this technique.