Bodywork looks lovely there in grey
The good news, is that the bodywork is definitely the hardest bit, so with that done you're in a good place.
I don't think you'll necessarily find a guide as such. You could read through some of the build threads on here for ideas as to how people tackle it.
There's no particular order necessary, though it makes sense to work on one sub-system of the car at a time, then when it's done you can bolt it on to the car and it wont get lost/damaged. As you've already got suspension on temorarily, maybe starting there makes sense? A rolling shell is easier to live with than one on blocks!
To me it makes sense to get all the mechanical bits sorted before you start on the shiny bits of interior and trim. You'll need to run the various control cables gear linkage, brake line and fuel hose through the centre tunnel in the car, so it makes sense to do all of that before you consider carpets / floor mats. Likewise you'll want to get the wiring loom run through the car before you fit the engine and fuel tank, as it runs behind both of these. It's perfectly possibly to do it with them in situ, but its just easier without.