If you have a 2000 with oil pressure gauge please read

I am trying to attach a "T" fitting to my oil pump to run an electric oil pressure gauge. The 00 is apparently different than other years as there is no "plug" to remove in order to install the T which will allow me to use the stock gauge and the new one. My question is what is the size of the stock sender (thread size), i thought 1/4" but now that looks to small.

if you have a 00 and have installed an aftermarket electric oil pressure gauge you probably know what I m talking about.

Thanks!