I've been messing around with 8-4 IL and haven't been able to get backwards wall jump nearly at all. In runs I've only done 2 frame wj, but I also want to try for 1 frame wj for 458 but in practice I rarely hit pixel. Is there a specific wiggle I should do, or a guide I should follow?

the recent setup found was a d+r setup. Giffi in his stream told me about it. i hope i got it right:

1. after a full jump from the frame perfect jump between the two pipes at the start of the room, you must hold down d+r in mid-air. 2.. hold d+r upon landing then jump at frame 232 (this is the sacrificing a frame part. the plus side here is that the walljump tends to be faster this way bc of subpixels/subspeed)
2. after jumping, you may now release d+r the proceed to do the backwards walljump

before this was found, i didn't really find solid setups for walljump. a tip that i can give you though is that you'll have to jump a bit lower. there were a lot of times where i just blatantly miss the walljump pixel. turns out that the wj pixel is lower than what i anticipated. the way the pipe looks like kinda deceives you of the block boundaries so just watch out for that.

also, make sure that you are not going up as u hit the wj pixel. u have to be either at the peak of ur jump or just at the start of ur downward arc

hope this helps!