I have got a 2004 VY series 2 Ute Ecotec and want to put LS1 or L67 into it. What would be easier and would I need an engineering certificate for either seeing as they are both standard engines for the VY?

In regards to which engine would be easier to transplant in place of your V6 ecotec, the L67 engine could potentially be considerably easier by far. I say this as the L67 engine would essentially bolt straight in as a replacement for the ecotec, coupled with the fact that you can even get away with using the ecotec wiring loom (slightly modified) and computer. The ecotec computer would need to be reprogrammed to suit the L67 engine though, which we can fortunately supply without any problems and would be a genuine case of unplugging your original ecotec computer and plugging in our new programmed one. In regards to the LS1 conversion on the other hand, your best bet would be to get a complete donor vehicle and swap all of the appropriate parts from that. Off the top of my head the K-Frame assembly, wiring loom, fuel lines and engine/trans would need to be changed etc. It’s definitely a big job. Both conversions, provided all of the appropriate factory components are used, would be legal. However, depending on the state you’re in, you may still need an engineer to sign off on the conversion. Your best bet would be to check with your local transport authority for confirmation.