Mounting help for 3G alt in '69 4x4 460 starting with bare block

[carbine2]

Hello everyone. After ignoring this project for a couple of years I have been talked into getting back to it. My nine year old has turned into my project manager and is pushing me every day to get it done. Heck, he is doing most of the work.
Anyway, what I've run into is trying to figure out what brackets I need to mount a 3G alternator from a '96 mustang onto the 460 we put in the '69 F-250 crew 4x4. The engine had no brackets at all so I don't have anything to start with. It looks like low mounting will hit a cross member so high mount may be the only way. Does anyone know what part number a ford bracket would be? Or what year of 4x4 I should be looking for parts off of?
I've been all over the forums and found a lot of good info on wiring but nothing about mounting it to a 460. Mostly FE motors.

Thanks
Allen

[carbine2]

BTW, here is my youngest putting a PMGR starter in for me. I just had to tighten it down when he was done.

[carbine2]

My kid and I drove to a yard an hour or so south of Portland and poked around for parts today. We found a bumpside with a 429 and robbed it of it's alternator hardware. It was a 2x4 so I suspected it might not work for mine but what the heck. It is better than the one I don't even have. After driving around in Stayton for a few, showing my kid the sights in the small town I grew up in, we headed back to try the parts on. The 3G fits nicely on the brackets but is nearly touching the cross member. The pulleys swapped from the original unit easily using the lock nut as a spacer.
Unfortunately, when I went to clock the alt body, I turned stupid and forgot to take the contacts out first and broke one. At least they are easy to replace on a 3G. They bolt right onto the back as a unit.
I am still interested in any info on brackets that work better but I am making progress.