I apologize in advance for any redundancy with the previous replies;
I think what I'm seeing in the OP's original picture is a steel 90 degree fitting like maybe a AN914, followed by a union, followed by a straight hose end. A AN822 elbow in steel would be a simpler solution here, but I'm guessing you can't screw it in because it will hit the accessory case, which is why you've got this setup.
If thats the case, and you just want to re-clock what you've got so that the hose comes at the fitting a little higher or lower, then yeah, you can do that without changing anything.
Remove the union so that you have room to unscrew the 90 without hitting the accessory case, remove the 90, clean the goop off the threads of both the fitting and the engine side, apply new goop, and reinstall it clocked however you want.
There is guidance on how to install fittings like this in Van's section 5 instructions, readily available on vans website. I would strongly encourage you to review these before you dig in.
Basically, apply the approved thread sealant of your choice to the fitting, NOT the hole that it's screwing into. Skip the first two threads so theres no squeeze out on that end to potentially get into the engine. Tighten finger tight, then wrench it 1.5 to two additional turns. Any less than that and you will potentially have a leak, any more than that and you can damage the engine side.
The end that's screwed into the engine is a pipe thread. They don't bottom out like an AN flare. Instead, they are tapered at the tip and get bigger toward the base to create an interference fit. This is why you can break stuff if you go all cave man and keep cranking them down more than 2 turns past finger tight.
Because of the design, there will always be a slight leak path around the threads, so you have to use thread sealant. Typically, it's bad form to readjust one after installation, because depending on the type of thread sealant used, you can break the seal (for lack of a better description) and it will start leaking.
Use one of the sealants called out in Vans section 5. Under no circumstances should you use teflon tape on a fuel or oil system because tiny particles of that tape can get cut off during insertion and find their way inside the engine where they can block passages and cause all sorts of havoc. There was a fatality RV10 crash a few years ago because the owner didn't know this or ignored it and used teflon tape on a fuel fitting.
FYI- a more elegant, but also more expensive way to redo this would be to just come off the accessory case with a steel 45 as Tom suggests. Whenever you have a 90 thats parallel to the crank shaft, the engine flopping around combined with the weight of the hose has the (admittedly small) potential to loosen the fitting causing annoying seeps. Using a 45 instead of a 90 will pretty much eliminate this.
They make a 45 restrictor fitting. As others have mentioned, it will dampen potential instrument fluctuations and also buy you extra time to get on the ground if you have a hose burst (also an admittedly small possibility with todays modern hoses). They aren't cheap, but I'm a belt and suspenders kind of guy, so all my oil and fuel sensor lines incorporate them.
Sorry for writing a book here, hope this helps.
