If you have a stub shaft that bolts in the top gear of the pump in place of the silent shaft, you're set, if not, you'll have to find a new press-in plug/stub shaft to close the oil passage in it, or you'll have no oil pressure at all.

My 2.6 also had a delete kit put in by a prev owner, still runs good, and it might have saved it from a catastrophic timing chain explosion when the drivers side chain guide came unglued and was flapping around.

It's up to you if you put the shafts in, but they really are only there to reduce the vibration that you feel in the cabin, which is moot point on a trail rig IMHO.

Again, be SURE to check that the oil passage in the top (non-driven) pump gear is plugged with either a solid plug, or a hollow brass sleeve, or a stub shaft!

Easy way to see if all is well, if the pan is on and has oil in it, is to put an electric impact gun on the nut on driven side of the oil pump, with the chain off, and spin her up. You should peg the oil pressure gauge, and have some spray-out on the relief valve on the side of the pump.

Messy, but worth the peace of mind.

Hope some of that helped.