no they do not fit and unless you get lnf, or g6 , or gmpp upgrade knuckles, there is insufficient meat in the stock lsj knuckle to enlarge it to fit the grand am bearing. Reverse engineering this wont work. The grand am hub reads abs fine but it takes a larger output spline axle cv bell and that means a special shaft( I had mine made for the race cars at considerable expense out of 300m steel) or install an LNF axle (direct bolt on)
redrilling a new pcd is possible in the stock bearings, but can be difficult and certainly not a 'drill a few holes with my black and decker' job.
The rear bearing needs to be faced on the back side otherwise the stud ends wont fit straight on the hub itself when re drilled.
do it right or not at all.... its a great conversion which then allows you choices of all sorts of really good wheels available in 5 x 114.3 ( 4.5 pcd) which is a Mustang pcd by the way.
but cost is a factor. The folks on here are the second, third or fourth owners these days and who has money to spend up to 2000 dollars on the conversion, new wheels and new tires for a car that cost 3-5000 dollars in the first place?
ebristol, shab, myself etc, these guys are rare, spending thousands of dollars on a 9 year old car not made anymore...