The front is best, but you might have to try it at the end if it interacts badly with any fuzz or overdrive pedals you might have.

Also, if you have any Boss pedals they have a buffer inside so you only need a separate one if all of your other pedals are true bypass.

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Fender Strat
Fender Blacktop Tele
TB FX Loop/Channel Switcher > (in loop) > Mojo Hand Analog Filter > EQD Dream Crusher Fuzz > Subdecay Liquid Sunshine > Frazz Dazzler > Line 6 M9 > EHX Memory Toy > (end of loop)
Soldano HR50+

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