So I've been researching James Herfield's rig and I see he used to hook up a Mark 2C+ To a marshall head. So the mesa is wired as a preamp and the marshall is used as a power amp which runs into a Mesa 412. Can anyone explain how this works and is it something I can do with a Rg1003 and a jcm2000 dsl100?
Going from "line level out" to the input of another amp is pretty safe. Going from "speaker out" to amp input will probably result in a visit from your local fire department. I used to stack SS amplifiers while working as a DJ as a poor-mans bridge but tube amps are different animals. Not recommended.
"Your sound is in your hands as much as anything. It's the way you pick, and the way you hold the guitar, more than it is the amp or the guitar you use." -- Stevie Ray Vaughan

"Anybody can play. The note is only 20 percent. The attitude of the motherfucker who plays it is 80 percent." -- Miles Davis

Guthrie on tone: https://www.youtube.com/watch?v=zmohdG9lLqY
Not sure how many marshalls there were back then with fx loops, but Id imagine he took the "fx send" signal from the mark 2c and plugged that into the "fx return" of the marshall head. this woulld be the proper way to use an amp as a preamp with a separate poweramp.

so basically simple guitar cable from fx send to fx return. Ive no clue how your solid state amp would handle being unplugged from a speaker, so Id leave a random crap speaker plugged into the rg1003 and lower the volume to 0 on the rg1003. the marshall will provide all the sound you need.
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