as long as theyre visible, distinguishable from left to right, do not obstruct anything, are not in any way a hazzard and are secure. I dont see a problem.
There are micro indicators on the market at the mo. theyre tiny but flash brighter to compensate for the size.
They might give you a bit more clearance, but may be more fragile due to the minute size.
OR
Have ya thought about grafting some old moggy 1000 indicators on?
theyd be well tucked away behind the no. plate until ya needed them!

just pull on a bit string and out theyd pop!
Im a genius