Troubles with my '99 S-truck at start-up has lead me to learn that sometimes the injectors on it's LN2 get stuck & hang open, leading to the condition of the sound of a misfire & kickback occasionally. A friend says he can lay hands on a set of spares from a LS-engine build he had hand in, but needs to know first what type of driver (electrical) connection they use & what size (lbs-hr flow) they are so we can be sure they're not too-much for my app. Keep in mind, the engine is fully production-stock. And the most it may ever see is a set of 1.65 rockers & a good header... time & money permitting.
Go beyond the "bolt-on".
i know that the injectors on the later Ln2 in the J's were 19lbs per hour flow rate and i believe high imp injectors. Im not sure if that helps you, but thats the info i have off the top of my head.