Measurement wise, yes.
You should check how easy the process of removing the old arm would be.
Curiosity: why would you change arm with another from the same maker and the limitations of the same length?
I'm asking since I'm in a similar situation (8.6" Pro-Ject arm, on an RPM 1.3) and I came to the resolution that I'm going to either invest on a new, better cartridge or I'll change the entire vinyl rig with something that is born on a higher level (e.g., Rega P8).