You may want to consider a high compression overbore (larger bore) piston/cylinder kit for your "B". A piston/cylinder kit gets you new piston pins (with the new pistons) that is a big advantage.
You may want to get a "I & T Shop Service" Manual for your "B" They are very helpful. Most "TSC" Stores have them and I think that they are available from suppliers on this site. There are a lot of "small things" and/or "details" that are different on the AC "B" engines than on most automotive engines.
Be sure you understand the shims on the connecting rod and main bearings that control the "crush" of the shell insert and that you are confident that you know how to install and adjust them. (The I & T Manual explains this very well - para 97, page 21.) Tightening torque values are also important (page 4).
The I & T Manual indicates that the camshaft uses "three renewable split type bushings". (I have seen both split type and solid type replacement bushings used in "WC" engines.)
Be sure to clean all of the "sludge" out of the "hollow" camshaft (that is the "oil gallery" for the engine maim bearings).
Also be sure to clean the hollow rocker arm shaft, the grooved rear rocker arm support stud, and all oil holes in the block and the external oil lines.
Be sure to used the "string wound or fiber packed" oil filter with the removable "stick" in the center. You can also want to fill it with oil and "soak" it in oil before installing it to help bring the oil pressure up quicker.
If you want to "up grade" the engine oiling system you may want to investigate modifying the crankshaft to provide oil to the rod bearings. (Number 1 rod bearing from the front main bearing; Number 2 and 3 rod bearings from the center main bearing; and number 4 rod from the rear main bearing.) This requires "drilling" the crankshaft in four locations. This is like a "CA" crankshaft. If you do this remember to "plug" all of the "rod bearing oiling holes" between the lobes of the camshaft and in the sides of the rod bearings.
Wheather ot not you decide to do the above "upgrade" to the engine oiling system, you may want to increase the diameter of the holes in the center bearing journal of the camshaft. If you think about having the same oil flow area of the holes in the center cam bearing journal as in each of the front and rear cam bearing journal oil holes, it does not seem "right". This means that there is twice as much area for oil to leave the hollow camshaft as there is for oil to enter the camshaft in the original design. This "might" be the reason that the front and rear main bearings usually show more wear than the center main bearing in well worn engines.
If the engine was burning a lot of oil it may need new valve guides and perhaps new valves.
You might need to check and regrind the rocker arm contact areas (where they contact the valve stems).
You can also "pump" oil into the engine through the oil fitting "T" on the side of the block prior to starting the engine. Or you can "spin" the engine with the starter or with a hand crank (with the spark plugs removed) to get full oil pressure before you start the engine the first time after overhaul.
Good luck on whatever you decide to do, Gordon in IN