If it's an original scx10 (not a 10.2) the best thing you can do for increased steering angle is the "XR mod" which allows you to use XR10 (or AR60) c-hubs and knuckles, along with XR10 universal joint axle shafts. With modified shafts, you can get up to 70° of throw, but still get around 50° with stock XR shafts. To accomplish that, you'll need to modify your axle housings to accept the new c-hub, which is easiest with a set of Beef Tubes
https://www.beeftubes.com/store/p56/SCX10_XR_MOD_BEEF_TUBES_-_NARROW_-_BRASS.html
All that said... you're almost better off just switching your entire axle assemblies to 10.2's at that point. Probably could be done for similar cost, have good steering already, lower gearing, smaller pumpkins, high pinions, etc.
If you want to stick with the basic scx10 design, the 8 degree and 11 degree c-hubs are referring to the amount of built in caster. I prefer more (so I'd choose 11°) partially because it allows you to point your pinion up a little more.
There are also "8 degree" c-hubs that are referring to the king pin inclination (like an XR10, Wraith, Bomber, and 10.2 use) which reduce tire scrub and, depending on caster setting, can really change the position of your tire's contact patch when steering. This style requires you to change both knuckles and c-hubs with matching parts (8 degree and zero degree won't work together.) This is basically accomplishing the XR mod, but with scx10 axle shafts, the biggest problem here is finding scx10 shafts that are worth a crap. There are kits for this
Pro Steering Conversion Kit for SCX10 (Silver)
There's a lot more that can be done, but hopefully that gets some ideas going for you.
