This is sorta the gold standard in the US for driver training...
http://pitfit.com/e-...ining-programs/
Yes, I'd found my way to PitFit and their sister site "safe-is-fast". Much of the above is based around the publicly available content from Jim Leo. At some point, I may look into one of his advanced 12-week plans, after I'm ready for that. But, I'm seeing what I can glean from public domain sources first.
I noticed that he sells "Indo Boards" on his site, and you can see them in his videos. So, I recently made myself one ($20 in material vs. $150 for the real thing). That thing seems to have a lot of promise for racecar specific balance! Its a very fluid motion when done right, and requires a fine sense of lateral balance, specifically. The motion and sensations seem very similar to balancing the racecar through the corner. Eventually, I may buy the Indo inflatable thingy that allows you to work on 2-axis balance (lateral/longitudinal)--which I would expect is even more racecar specific training.
One of the most important things you can do is learn to focus when stressed and tired. So do mental exercises between sets at the gym. This has helped me tremendously over the last year.
Yes, I've found performing hand-eye drills (juggling or reaction ball work) following intense workouts to be difficult, specifically due to the need to maintain that laser sharp focus. In particular I've found juggling continuously (just basic 3-ball underhanded juggling) and trying to keep it going for as long as possible to be very difficult, post workout. Its easy to lose focus (zone out, etc) for just a moment and then it gets away from you. This seems to be particularly true as my physical status transitions back down to normal...as the HR and breathing is slowing down, and I start to feel more normal it is very easy to "relax" for a second (the "ah, that's better moment)...then I toss a ball goofy or take my eyes off them for a moment....next thing I'm picking them up and starting over.
When I want to actually train hand-eye specifically, I do the drills fully rested...and try and force more new/varied stimulus (over-handed juggling, alternating high/low, etc...things that make me react and move my hands in space to unpredictable locations). When I want to work on focus and concentration...I mix them with my workouts, and work more on consistent repetition.
I was an ultra-endurance athlete for 25 years. So, I've spent 10s of 1000s of miles doing mental math problems just to keep the boredom away. I like to do long division of decimal numbers in my head. Something I started doing while weeding soybean fields as farm hand back in the early 90s.