you need to purchase a real crimper,not the $5 style...you need a good ratchet style-these are not cheap...it's like battery terminal tools,my crimpers were in the area of $400,these have the dies to properly crimp all the terminals,most people do not have this style.
soldering,as i've stated previous,is not an accepted method of making connections in the marine environment.

remember all this when a guy who works out of his truck pulls up to work on your boat....