20" fit fine, most people wont lower it much on them, so it makes them look taller, and toy like IMO also. There is gonna be a small sidewall, so be prepped for a firm ride, HOWEVER, quality susp components will help ALOT. If you like the soft OEM ride , dont lower it or do big wheels. 20 year old springs vs quality tuned lowered products are night and day different and what some ppl call harsh is just removed OEM slop, and real road conditions. (Remember tires and susp are just giving feedback on the road, how much do you wanna know?!)
If you get the correct plus size tire and offset wheels you can lay it down real low, and get the Foose look that some of us like and desire. 275/30-20 rears on 10" and 245/35-20 on 8.5" fronts will work well, and find a reputable shop to do back space measurements, it'll save a big headache later. Also, if you use spindles the front offset needs to be differents vs just using drop springs. You moved the mounting point further up in the "travel arc"....
(think of it this way, if its a 26" wheels pkg w/ tire based on OEM sizing regardless of wheel size, a 2" drop spindle raises the wheel/brake assy up, and leaves the other points at the same place. It essentially makes the car see the wheel as 15" top half, and 11" lower, kinda off center of design thus maybe a clearance issue w/ fenders and so forth ( although still a 26" pkg), instead of the designed 13"/13" split off OEM spindle and A arm measurements.)
Good luck, hope I didnt confuse you , and post pics once done!