Should i de-smog?

Good idea buying the Holly carb lever adapter as it will ensure the kickdown linkage/rod has the correct geometry. I suspect it's probably similar to Edelbrock's 1843 adapter but for a Holly. Even with that adapter though you should still double check the kickdown lever that goes into the transmission is all the way back once you've got everything back together. Mine wasn't even with the 1843 adapter and I've summarized how to check in it in my LD4B thread.