Tara,
Cutler's book includes a support protocol, in addition to chelating supplements, which although less specific than the SMP is similar in what is trying to achieve.
With amalgams, he suggests starting with support until they've been replaced, after which chelation may be added.
The basics include Vitamin C, B complex, Vitamin E, chromium, magnesium, milk thistle and flax oil. There are additional supps depending on individual needs.
I did both but started with methylation first, with a multi-minerals (I didn't take the standard multi) plus chromium and selenium, milk thistle and phoschol as that seemed to cover my needs better.
From reading the book I got the impression that chelation side apart, everything else is supposed to suit individual needs.
All the best.