So I am also looking at buying some after market gauges for my prelude as i'm beginning to build her up, does anyone know the fuel OHM's for full and empty on our tank?

I haven't ever seen that published anywhere. I would suggest that you just grab a DMM and measure the resistances for yourself at the connector. There is an access hole on either side in the trunk above the fuel tank. Lower the rear seat back and lift the carpet. I don't remember for sure which side has the fuel sending unit. The online service manual will tell you that though.

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1991 Prelude Si ALB
2015 Subaru WRX
2004 GMC 2500HD

Fuel level sender is on the right side. That is right as in passenger side in north america.

So with help I have it and found the measurement but does anyone know how to remove the sender from the tank itself? I see no bolts and I would prefer not driving until I run out of gas to find out ohms on empty :P thanks!

First order a new gasket. Once you crack the seal the old gasket wont seal right again. Once you have the seal, since the proper tool no longer exists, use a py bar and a hammer to tap on the retaining ring that licks into the top of the tank. Tap it in a counter clock wise direction

Check out page 16-89 on the 3rd Gen Repair PDF. If you don't have a copy, here's where to get one. It's searchable too!

3RD Gen Troubleshooting & Repair Manual (Searchable PDF)

It has the Full / Half / Empty resistance readings

Now, If you are going with Aftermarket Gauges, You may not be able to find one with those exact readings. A LOT of the aftermarket gauges have their own matching sending units. I know Summit Racing carries sending units of different diameters and lengths to fit various gas tanks. Let me know if you have any additional questions, I will be glad to help!

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1989 Honda Prelude Si - Daily Driver (So far, So Good)
1970 Buick GSX Clone - In progress
1988 Chevy Suburban TravelQuest - WorkHorse
1978 Buick Skylark - Sold

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