I'll have to go watch a replay to give actual speeds, I always use manual trans and that allows me to judge my corner speeds by which gear/rpm range I'm in. I know the first corner at Forest is a third gear corner, I always slow quite a bit and turn in late but sharp, apexing to the inside by mid-corner so I'm full-on throttle by exit, then I hit forth gear just as my front wheels lift over the following hill.
But IMO, it's the last two left-hander's that make or break the lap times there. You really need to carry high speeds through both of them to set the times posted in this thread. I always try to approach each of the last two corners as fast as posable, at the last second I'll give a tap of the brake with a quick downshift and cut into the corner, immediately back on the gas and get back to 5th gear as soon as posable. Usually back into 5th before the downhill in-between them, and before the top of the hill on the final strait. And careful with the outside rumble strips on the final turn, it's necessary to touch them, but if you use too much of them it'll send you strait into the pit wall.