#2
To go from active to passive, you just need to also change your volume and tone pots. Actives also have a different input jack, but you don't really have to change that, just wire it correctly.
#3
^ This. Give the EMGs a try, see if you like them. If you do want to switch them out and you are dead set on passives you need to switch the pots to 500K pots. Though I have heard good things about the EMG57/66 set too, very PAF-like. Switching to those would just be a quick discconnect and reconnect.
Gibson RD Silverburst w/ Lace Dissonant Aggressors (SOLD)
Electra Omega Prime Ceruse
Fender Franken-Jag Bass

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Laney VH100R
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