Yes, I've done this MANY, MANY times in my life... Generally with Les Paul "style" guitars.
Epiphone LP Standard- dropped in Duncan 59's, also tried Pearly Gates to try to "sound like Billy Gibbons"
Bently LP - this guitar would never even intonate it was so cheap, it was also a boat anchor, but I threw a set of EMG 81's in it to sound like Metallica, (this was in the late 90's when I was in High School and still couldn't play guitar)
1961 Fender Bassman - my "dream amp"... I'd always wanted one, and always drooled over them. Then one day I got the crazy notion to trade in my Badcat Cub on an old 6G6 blonde Bassman ($2000). So I traded the amp plus $500 to buy this 61 Bassman, even though the Bassman sounded TERRIBLE!!! I found out in the cabinet, one of the speakers was blown, and the other had a voice coil rub, so I took them out and replaced with Vintage 30's (for a Setzer tone)... Then I thought, huh, maybe the head needs work, sure enough it did, caps were blown, etc. So $300 later, I had the head back, it STILL sounded TERRIBLE!!! I then decided to have another tech verify the circuit, he said it was perfect too. So I took it home and decided, gee whiz, it MUST BE THE SPEAKERS!!! So I bought a pair of Weber 12A125-O's (another $200), to try to make it more period correct, and try to tame some of the ICEPICK Treble that that amp had. Finally after playing it this way for a while, I realized that this amp just wasn't for me. I sold it, head and cab for $1200. I lost a STAGGERING, $1300+ on this amp. That day I swore off vintage amps forever.