They are pretty knowageable. Make sure you check whether they are automotive or screw-on terminals. Check the dimensions out

(I had someone tell me I had four 8D's when they were 4C's ;^))). I said are you sure? They said, "How can you questions me?" The installer (that was doing other work paid for the reshipping, but it was a pain in the ass because they had already pulled-out the old ones when they discovered they had messed-up. The 8D's are VERY heavy. The 4D's are just HEAVY.

p.s. - If you are going to have a separate engine starting battery, I recommend the Optima. They are small, powerful, and very forgiving.