2001 black front rocket set up help!

[car23]

Need baseline setup for 2001 black front! Run limited steel motor. How do u measure rear end location in car . I saw some crate info on here but i need to work toward super set up. Car has twm welded bird cages. I see on a thread on here that it gives a difference between bird cage measurements. Could someone give me a figure from tube top so i could eliminate this diff from equation. In a hurry just got car as a backup for this weekend

[PA Dirt Fan]

The original welded TWM cages were 6 1/8 at the RR from the cage to the bottom of the RR frame rail.

The rear end side to side measurement is 16 1/2 with a 2in frame and 16 3/4 with a 1 3/4 frame. You measure it from the side of the plates on top of the rear end over to the inside of the RR frame rail. I'd say from that year of car you have the taller purple brackets on the rear end there easy to measure off of if you don't and have a odd ball or the new style rocket plates that are shorter you need to make a L shaped tool out of some scrap to measure the side to side with the short brackets you get your measuring device at an angle and it throws the side to side measurement off the tool will get you up higher and straighter Those 01 black cars were good cars

[car23]

that is measuring from the top of the birdcage ear to the bottom of the frame. am i correct i want to know the difference in the twm bird cages i will give them (twm)a call tomorrow. prob go ditch liner type for bearing anyway. i cant stand a hanging up rear. i had trouble on the scales i couldnt get the rf ride heigth to work. started tightening up on spring before i got gap. i will get my book from rocket this week