Kurt is right. KISS (Keep It Simple Stupid).
Best rule of thumb (you've probably already heard it 1,000 times and will hear it more) is that you should get the best sound you can onto tape, disk, whatever.
Start with your sample.
What is its purpose in the track? As is, absolutely "raw", how does it sit in the mix? Tweak it out until it is as close to what you want as you can get it.
Still not good enough?
Now is when you put it through the amp. Choose your favorite mic. Put the track on a loop and work with the amp to fine tune the sound. Then work with the mic placement. Yeah I know, it's a pain running back and forth between the studio and control room, but you're the one who wanted to do this. :d:
It's hardest the first time, but you will get to know your system and room(s) better as you do it more often. Remember to have fun and experiment, experiment, experiment. Thomas Edison discovered 1,043 ways NOT to make a light bulb, but all his "errors" provided lots of new ideas.

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