I'd suggest that if you would like to install a lever arm system, even though space is rather tight , it is very feasible.
I have installed lever arm systems in my SliM and SliM2 Footys and can manage to acheive an effective arm length of about 50mm (from center of servo to sheet take-off loop). The key is to offset the servo to the point where it is very nearly touching the hull on one side to achieve sufficient clearence for the arm swing on the other side.
I have also used lever arm systems in my RG65s where, although my narrowest beam is a rather wide 110mm by todays standards, there is plenty of room to spare without the need to offset the servo much beyond the centerline.
If you're interested, I'm happy to post some pictures, however, .........
I've been locked out of this forum for about a year and have discovered a few friends have also been locked out but none of us are aware that we've contravined any regulations!
The only reason I'm accessing the forum right now is that I'm on holiday and, on the off chance, having logged in on a different computer I dicover that I can gain access!
Regards to all