I am looking for a pedal that has the early ZZ Top sound, think La Grange, Brownsugar, Tush etc.
Right. Early ZZ Top is Les Paul, or sometimes Strat into cranked amp. It's not a very tough sound to get, but it's not a sound that comes from pedals.In the early years, it was a '59 Les Paul played into a 100w Marshall amp - I don't think he used any pedals (or very few) at that point. Based on that, I'd look at some of the Marshall-style pedals, but realistically it's tough for a pedal to recreate what a LP into a 100w Marshall does.
A lot of it is Tweed Deluxe too. A Brown Deluxe & Tweed Deluxe rig with a Les Paul, Tele, and Strat could cop most ZZ top tones. That said, there is a lot to do with those fingers.In the early years, it was a '59 Les Paul played into a 100w Marshall amp