Kevin,
The Clifton and Stanley referenced in the previous posts are different animals. The Stanley(s) are essentially metal alternatives to the moving fillister and would do a good job at hogging out the majority of the rabbet.
The Clifton combination plane could do the whole job but doesn’t come with a fence and is best for fine tuning and smoothing the rabbet.
As I said, I choose to use a wooden moving fillister plane but have the other variations. If you choose to play with the Stanley 78, my suggestion would be to get a complete and fully functional junker copy, remove the rust, lubricate it where necessary and sharpen the blade. A more expensive copy won’t teach you anything more or enable you to do a better job. Don’t buy one without the fence.
If you think of getting a better condition copy, I think the Stanley 78 is still made in England and was made in the U.S. from 1885 – 1973. Every workman at the time had one and this is one of the tools that helped Stanley build their fortune. If you see the British Record 078, it has a bit more mass and seems to handle better. Better yet would be the Record 778 as many people prefer this plane over the #78 due to the two arms for the fence and the cutter’s adjuster.
The best vintage variant of this kind of plane is the Stanley #289. This is one of Stanley's nicest planes, looks a lot like the #78 except with the noticeable difference in the cutter's width and that the cutter is skewed. There are also the two scoring spurs, and a depth stop and fence that can be positioned on either side of the plane. With all the original parts this can be an expensive collector’s plane, but many of them come at a bargain price because they have the fence from the #78.
As for me, if I were buying a metal version of this type of plane and planned to keep it a while, I would buy the Lee Valley as they put a lot of time and effort in making a superior modern variant of whatever inspires them. If you still want a Stanley, I could probably make you a good deal on one.
As for the Clifton 3110 “Combination Rebate, Bull Nose and Chisel Plane” mentioned by RMW, if you are serious in getting one I have mine for sale and will make you a good deal. It is in essentially mint condition with all the original parts including the spacers and even has the original waxed paper wrapping and blue box which is still in surprisingly fine condition.
I need to raise some money before my CXS and Carvex show up on my credit card bill in June, so I am selling some popular quality tools that I haven’t used in a while.
Gary