I wish it was just as easy as buying a pedal and sticking it in front of or behind the preamp( some have better luck then others) but IMHO and only My Opinion, It takes more than just turning knobs. Jerry's reverb was dialed in by a guy (or guys) that knew and fully understood the reverb circuit of the Twin Reverb. A good pan with the correct Transducer impedance's is a big part of it. His sound did not just come by luck of the draw or by picking the best out of the lot, although the latter is where to start. It was executed to perfection and that is why it is so elusive.
Those that have tried pedals, digital, analog or tube circuits to include myself, have generally only been happy with the results. No one has come forward and said "That's It", at least none that i have seen pertaining to this subject.
Also, Jerry's ADA 2FX was modified by Healy to have the Wet/Dry Mix and Multiplier potentiometers remote out to foot pedals. You will here this first right here, but in his 90's rack the 2FX was not in his OBEL. It was placed in The Trio's effects loop, before the Tubeworks Reverb, ALWAYS in the circuit. Foot down was Dry, so it would have went:
end of 92 - 93 trio>ada 2fx>tubeworks tube reverb>ada cab simulator or mc2300>JBL's or other.
sometime in 93 - 95 trio>ada 2fx>tubeworks tube reverb>sound research ELF/ Reality Amplifier.
https://www.mickeyhart.net/news/all-abo ... -baby-5211
Just to note, not sure most know that the 2FX also has gain available at the input of the unit and the output of the unit, so when he used it Dry that was another couple Gain stages he had available to tweak in the circuit.
Only my opinion though, other may feel he did it or they should do it another way and they may be right and I may be wrong, I have been before and will again.
Disclaimer: I get paid to make, modify or build things for those that seek what i may be able to provide.