yeah I went through all of that too, it got very frustrating. went back twice for a "retune", blamed the fuel pump, cleaned injectors (again) eventually the lobe had rolled on the cam and only done 20k klms.
My new opinion is "don't do anything half ass". If you do the cam on an older motor...
I had a new cam fitted by High Torque on the gold coast with a cat back & tune and I came to regret doing the cam. should have just stuck with the exhaust & tune for my daily driver. The cam ended up stuffing out & had to get replaced and its been more difficult to start since.
I know it may be a needle in a haystack but a mate of mine is looking for a workshop manual for his 1995 VS 5.7L HSV Senator.
Not sure if one even existed?
But happy to pay if there is anything around.
I'm in the habit now of upgrading anything that breaks on Chinese stuff now and don't bother with replacing with the shitty parts. I had a new hose made by Enzed & had my sparky replace whatever was needed at the time.
As mentioned the fabrication & mechanical seems very good (I'm a fabricator...
I've had the single phase Hero hoist for a year or 2 now. mechanically its all great just blown a hydraulic hose and a small electrical issue but the hydraulic pump set up would be fairly generic I recon.