There is no direct or simple answer to this question...
My musical tastes have changed dramatically over the past few months. I'm listening to different music. I'm finding inspiration in a different place. Power chords have been replaced by fast arpeggios on groups of single strings. I admired many guitarists as a young musician, but today, I find more interest in the strategy behind a band, it's concept, music, marketing, promotion and commercialism as opposed to just the music. As far as inspirational guitarists are concerned, I would have to limit my response only to those currently living.
Personally, I find no equal to John 5 in speed, technical proficiency and versatility. Second in line would be Jason Hook. His session work is beyond description in the areas of versatility and technical ability - far beyond his work in 5FDP. Jimmy Page continues to inspire me with his stage presence and whimsical demeanor. His energy and style are inspirational to say the least. Tony Iommi - such tone can be described as simply magical. His pose, stage presence, relaxed demeanor and hard hitting tone, riffage and arrangements are spellbinding.
But then, what about solos???
While I admire many for their prowess as a rhythm guitarist, I am not always inspired by their lead phrases. As far as leads go, I would have to give the crown to Dio-era Vivian Campbell and Doug Aldrich.
However, while I can draw inspiration form these, my own style has begun to change dramatically - to such a degree - that I even find myself surprised by what I hear coming out of my amp at rehearsal. It's furious, heavy, dark, foreboding, evil and immensely rewarding.
Membership in this most recent band has totally changed me musically...
Ok, back to the point...
If I were to choose only one as inspiration for rhythm work, it would be Tony Iommi
If I were to choose only one as inspiration for solo/lead phrases, it would be Vivian Campbell
And, currently, the band that is absolutely blowing my mind overall is Ghost.....