Lap Indicator Rule <R18> Clarification

[t-raum]

Last night we realized that we did not leave a place for the flag holder. We were reading through the rules thought we might have solution, but the rule <R18> is not very specific on what the "must be visible from above" clause exactly meant when it was refering to the lap indicator position. I was wondering do we need to have a 2" radius half cylinder that extends all the way up to the top of the flag or just up 2 - 5" around the flag holder. If anyone could help us out with this it would be greatly appreciated. Thanks and Good Luck to everyone!