Here's a quote from an interview he did. "Frankenstein" is the maple fretboard P he put together:
“I used Frankenstein through Hiwatts for the whole of ‘Tommy’, ‘Live At Leeds’ and ‘Who’s Next’ but by ‘Quadrophenia’ and Who By Numbers I was playing Gibson Thunderbirds. I felt I was getting stuck in a rut, using all the treble.
I got that quote from this website, which thankfully has just been restored after a database crash. An excellent archive for all things Who:
http://www.thewho.net/whotabs/equipm...ear-67-71.html