I would like to replace the standard string head with either a tap head, pre cut string head, or 3 blade quick change. The "universal" "fits most models" type didn't. I currently have to disassemble the head to get more string after it breaks (which is often) and have lost the cover bolt in the grass when doing this. I use .105 string and do some heavey cutting along fence lines which include some burdock, etc. Any one have a part number / brand they know would work