Busted power steering pump - fluid

Hey guys, mysteriously my power steering pump has shit itself on my EL Fairmont Ghia, after sitting there for about a month or two with the occasional drive around the block, originally it leaked out the rear high pressure hose and toasted an alternator, so I replaced the hose and the alternator, and now its leaking from the front into the new alternator, GRRR!

Its also leaked onto one of the cooling system hoses and it has swelled up.

I'm going to replace the pump with a reco unit and I know EL/AU suggests this Valvoline power steering fluid, which I do indeed have here, but would it be worth running fully synthetic ATF like Castrol Transmax Z in the power steering system instead with the new pump?

I'm going to use it in my T5 when it goes in so I will have some spare left over.

I run Dexron III in mine. It's all good. I'd just stick with what is recommended - it's not likely that Ford would have used anything special in the cars when they were new.

Did the EL's not have a special, speed sensitive pump though? I was under the impression that the Ghias got it.

Yeah mine has that pump with the speed sensitive steering

I took the pump off, easy job.

http://img580.imageshack.us/img580/8165/efo3.jpg

Engine bay looks a bit bare without it, it was hiding my extractors quite nicely.

Got my new pump in the mail today, I want to flush the system, that hose on the back of the pump, not the high pressure one, the other one with the hose clamp.

If I connect a hose up to that, would I be able to flush the fluid through it? I'm assuming its the return line?