Don’t look at the first number of 0w, the second number is the more important.
You never want the first number too high for a turbo car bc that’s cold temp rating. You want the turbo to flow to the turbo fast and a thin cold temp oil is the best.
So if you want to run a thicker oil. Do a...
Just do what you like. Enjoy the car man and not worry about the value on it. Some minor mods won’t kill the value and you can take it off when you sell it.
i wouldn’t do a conversation kit or redrill on te37’s IMO. Just get the correct lug pattern. I understand it’s a great price, but you will thank me later.
https://server.tunerassist.com/Downloads/Guides/Supra/Supra%20STG1%20Fuel%20System%20Upgrade%20Install%20Guide%20v1.02.pdf
Looks like you access it from bottom of the car.