Could always buy Good/Used from the junk yard to save some on the funds. As a matter of fact, I have an extra large case 3G alt. I no longer need. It is a 160 amp version from PA Performance. I switched to a small case on my set up. Then you would just need to get the controller.
follow up.
Yes you need a soft touch controller for an e fan IMO to avoid the amp spikes from a straight on/off with a thermostatic controlled switch. Yes you need a 130 amp 3g alt with any e fan.
The FAL 33054 is about $110. I've used it on many cars with success. Google Taurus fan and FAL 33054. There is a good install here and on the Corral.