Convert to a lithium battery. You'll be glad to leave lead acid behind. Huge weight savings, much better capacity and it's much smaller. Shorai is what sdt354 and I run and I can tell you we are happy. The battery comes with ton's of foam packing to fill in your battery box, so it's basically a plug and play upgrade.
An early adopter here, possibly the earliest mention of lithium ion batteries used by someone on the forum. Real-world facts on the weight difference, the size, and etc.
When/if my Shorai ever goes bad, i will get another one. It has by far outlasted the stock lead acid type. Hot or cold, long sits, no tender. It just works. Plus its small, light and my big one is...NO acid mess to deal with. Definatley worth the $$$ imo.