Ah yeah, definitely kept the EFI. I did the 8.1L install in 2008 and have about 25,000 miles on it since then. Pictures here. I’m collecting parts now to do an 8.1L swap in my Suburban too.
My Burb…’89 V2500, TBI 5.7L & NV4500 5 speed
I did a NV4500 swap into this one last...