4.88s and 35s are fine. You wouldnt want to go 5.29s unless you are planning on running larger than 35" tires any time soon. I have 5.29s with 35s and I feel it would be much more optimal with 37s. it will be a tight squeeze with the fenders but a grinder or a sawzall takes care of that 
A SAS is not difficult to do if you have the space, tools and a good knowledge of welding. You need a torch (can be done with a grinder or sawzall, but takes a lot longer) to cut off the IFS, a good welder to weld the hanger on and ideally a good lift to make things go a lot faster. Can be done without those "easy" tools though, but a good welder is mandatory. The hardest part about a SAS is coming up with the cash for all the parts. you want to go with the highest quality parts when you do a solid axle swap because your life and the lives of others are on the line when this thing hits the pavement. Check out marlincrawler.com forums, there are a LOT of SAS on their research board. Check that out to get an idea of what is invovled both cost and work wise.
A SAS is not difficult to do if you have the space, tools and a good knowledge of welding. You need a torch (can be done with a grinder or sawzall, but takes a lot longer) to cut off the IFS, a good welder to weld the hanger on and ideally a good lift to make things go a lot faster. Can be done without those "easy" tools though, but a good welder is mandatory. The hardest part about a SAS is coming up with the cash for all the parts. you want to go with the highest quality parts when you do a solid axle swap because your life and the lives of others are on the line when this thing hits the pavement. Check out marlincrawler.com forums, there are a LOT of SAS on their research board. Check that out to get an idea of what is invovled both cost and work wise.