Nice work getting it home! It is quite the sense of accomplishment when you succeed at moving something that massive and heavy into your own garage, usually with one helper and some pry-bars and pipes.
As far as phase converters, I only have experience with the rotary type. I built my own with an old 5hp motor, some caps, and a simple starter circuit. It works very well, and has not give me any problems. I used the plans that are available here: RPC I use it to power my manual Bridgeport and my 2.5hp vacuum pump that I use for my vacuum table on the Lagun CNC.
When I retrofitted my Lagun, I went with a VFD for the spindle drive, and would absolutely do it again! I bought a 3hp unit from automation direct for around $280, and it accepts single phase input. It is really cool to be able to basically set the speed on the vari-head and forget it, and do all of the speed adjustments through the software. I program the speeds for each tool I use in a part program, then the controller does the rest. It is a pretty cool feature to have, but you could always add it later.
For now, it looks like you will have your hands full (and dirty) with the cleaning! I have been there before. Something that I have found works very well for cutting the coolant crud is Greased Lightning. It is a water based alkaline degreaser, and seems to attack the sludge pretty well. Do avoid soaking any of the ways, or areas where it could get into bearing surfaces, as it is water based. Pretty fun to see how good you can get an old machine. Also, it is much easier to keep a machine clean, if you start with it clean. Also makes it much more pleasant to crawl around and work on it if you aren't getting filthy and full of metal slivers.
Post some pics of the progress.