What filter pedals will do a Mutron III close enough?
Also, other than later day Space jams, I associate very little delay with the sound of the Grateful Dead. I see that page says he was using an MXR Analog Delay in the 70's, but where? Off the top of my head I can't think of an example. Natural amp reverb, yes, set low, that's a consistent sound through all of his playing to my ears at least.
It's funny your range of tone is from 72 Tenn Jed to Franklin's Tower, it's really super clean to super clean through a leslie, so you are kind of answering your own question - you don't need much. A lot of his tone came from the pre-amp he used, the JBL speakers, his fingers, etc.
The OD-3, (and believe it or not, he used an HM-2), were 80's-90's sound. The MXR Dist+, is a good choice for 70's. Somewhere on this forum:
http://www.rukind.com/forum/viewforum.php?f=419
Brad Sarno says he made up a custom Dist+ for Trey to use on the up coming final run of Dead shows.
The new Beigel Octave Divider is pure Garcia tone, but too big for a pt-nano, so maybe a boss OC-2/OC-3, but you don't get that touch of Green Ringer, which is what I associate with Jerry when he used an octave effect, at least in the 70's (Fire on the Mountain live solos specifically).
Also, for 70's tone, you will be best served by a strat.
Proton as I mentioned above, and some kind of boost pedal will help goose the Proton as well, and maybe make up for the fact you are using a Princeton and not a (4) Twin(s). Although headroom might be an issue, I am guessing.
The rukind.com - Jerry Tone forum is a good resource, for all sounds Garcia. Those guys really get into the minutia of how to cop his tone.
Really? Uh, where do I sign up?!Brad Sarno says he made up a custom Dist+ for Trey to use on the up coming final run of Dead shows.
Delay, envelope filter, clean boost, phaser, dist/OD
Really? Uh, where do I sign up?!
Putting a JBL in that Princeton will get you a lot closer and won't cost any pedalboard space at all. Jerry played basically clean and LOUD. Classic Jerry tone is a Fender preamp into a McIntosh MC2300 power amp (600 watts of solid-state power!) into JBL speakers. Princetons like to grind, which can be cool but will top out before hitting Jerry-level intensity.