Scripted fields disabled because of security concerns - any alternative for Kibana 4.3.1

We have a huge distribution of requests and response sizes. So we cannot use response times directly but have to set them in relation to the request / response sizes.

Then, we would like to do size conversions:

bytes --> mega bytes
seconds --> milliseconds

Howto do that with scripted fields disabled. Not possible?

Without scripted fields, the only alternative would be to reindex your data and do the conversions while reindexing.

thanks @shaunak