After creating custom fields they are not in the position or size I would like

Version 4.1.1
After creating custom fields (Fill in one text area) they are not in the position or size that I would like. Where do I find the file that will allow me to change these parameters?

I assume they can be edited in a file like “/opt/rt4/share/Elements/EditCustomField” however when we do an update to RT would we not loose the change.