I don’t mean to hijack this thread, but here is another alternative for mounting a phone. It’s not my discovery, it was originally posted on usa7s.net by “KnifeySpoony” from the San Francisco Bay Area. Here is the link:
https://usa7s.net/ips/topic/13309-my-solution-for-phone-mount/#comment-121647
Since Caterham chassis are meant for either LH or RH drive there are steering column mounts on both sides. On LH drive the fuse box cover needs to be slightly trimmed to allow the small clamp to grip. For my car, the parts needed were:
RAM Mounts Double Socket Arm RAM-B-201U-A Short Arm Compatible with RAM B Size 1" Ball Components
Tough-Claw Small Clamp Base with 1'' Ball for All Industry Standard 1 inch / 25mm / B Size Socket Arm, Compatible with RAM, Arkon, iBolt and More (1''
RAM MOUNTS X-Grip Phone Holder with Ball
Jim