While researching injector options and knowing we can go from the S1 to S2 rails+injectors on the early model Q45's for better reliability, I came across this kit from Z1 motorsports for the early model 300ZX (Z32) which also shares the same style S1 injectors:
https://www.z1motorsports.com/z1-produc ... c166cc20f9
I contacted Z1 motorsports to confirm if this was compatible for the Q45/VH45DE and I got this response:
"Hello. Yes, the kit will work on a VH45DE. I just saw a S13 with a VH45DE swap running our adapter kit at Clean Culture ATL this weekend."
If you contact Z1 and say what you want, they will provide a quote of just the adapters and source your own injectors. They quoted me $215 for the kit without injectors (just 8 new injector connectors + adapters).
This kit allows you to stay using the S1 rail and provides adapters for the S2 injectors, new connectors and seals (if needed)
While its likely easier/cheaper to go with a S1 -> S2 rail from a parts car/junkyard. I feel like this might be a decent alternative if parts become harder to find, or maybe just for convenience in ordering a "kit" for anyone with injector issues that wants to also upgrade to the more reliable S2 injectors without sourcing the S2 rail.