I asked Craig about this last time I spoke with him. He has never done it before, but he was confident he could make it work.
He said the cart that goes in the Lyrik 170 is a 180 cart with a spacer. He said he could do a similar spacer for the 160 cart. that would give you 150 travel.
This would be a pretty cool fork for an Endorphin.
FWIW, the second fork cartridge that Craig built me was for my '05 5 spot. I asked him to make it just like the one he made for my el guapo. The lyrik I use on the 5 spot is a u-turn coil, which I have set on 5.25 inches of travel [roughly an inch shorter than 160mm, so 135mm of travel]. We did not discuss this; I felt from my experimenting with the el guapo fork at 5.25 inches that it would be fine. The result FAR EXCEEEDED my expectations. The 5.25 Avy Lyrik feels and performs fabulously.
Craig, sorry for the non-disclosure. You know how you can second guess and analize stuff beyond what is healthy. It works great; I would not have held you accountable for any disappointment on my part.