Looking for Horsepower Guesstimates on Friend's Build

We had something similar on the dyno here.
It had a little more duration, a Holley SD/850, Hooker 1-7/8” headers, and some minor bowl work on the heads.
It was like 540tq/515hp.

The last line on the dyno sheet was 5600, and the numbers were still going up a few hp per line.
The previous HR cammed 440 we’d had on the dyno experienced some lifter woes at 5800(Morel street lifters, plunger got stuck at the bottom), so there was a reluctance to run this one any higher, to try and prevent that from happening again.
Had it been successfully run to 6000 or so, I feel like it would have crested 525hp.
But at this point, that’s all “coulda, shoulda, woulda”.

My guess is the Howard’s/TF .600/.600 cam would have been worth upwards of 20-25hp more.