Funny, I used to haul around organs that weighed several hundred pounds. Now I'm wincing at the thought of a plus 30-pound arranger! Last organ I had, and I mean LAST, was FS500. What a beast. Then add Leslie, dollies, etc. No wonder lots of us have bad backs in our old age.
This was my "portable" organ/keyboard (Yamaha C-605p) back in the day...like your FS500 it was a beast, but it did come apart...and still weighed a lot too.

_________________________
Yamaha Tyros4, Yamaha MS-60S Powered Monitors(2), Yamaha CS-01, Yamaha TQ-5, Yamaha PSR-S775.