YOU SAID:

I've got a list as long as ma arm

INTO JAPANESE

私は腕だけでリストがある

BACK INTO ENGLISH

I have a list with my arm alone

INTO JAPANESE

私の腕だけでリストがあります

BACK INTO ENGLISH

There is a list with just my arm

INTO JAPANESE

私の腕だけのリストがあります

BACK INTO ENGLISH

I have a list of only my arms

INTO JAPANESE

私の腕だけのリストがあります

BACK INTO ENGLISH

I have a list of only my arms