For Sevilla and Brentford I parked on Townsend lane on the central divide in the middle of the road, facing the shops as you come in a few hundred yards off Queens Drive.
Walked up Townsend Lane, take a right on to Pinehurst Avenue then across Stanley park car park right to the ground.
There's around 40 spaces there if you're early enough, it's then an easy exit on to Queens Driver getting back. Probably about a 10-20 min walk depending how fast you walk. Postcode L13 9DN use street view on google maps to see the central parking, no restrictions there.
On Saturday for Forest I parked on Heyworth Street not far up from the One Stop shop (L5 4LH). That's a bit was closer but definitely busier getting out in the traffic going towards town.