Well, the decision to rebuild is based on the existing flaws with the engine. Sometimes one may find upon inspection, the engine may not need a complete rebuild, it may just need a cylinder hone, crankshaft polish and new rings, oil pump, timing chain and bearings.
If it REALLY does need a rebuild, , as noted above, let the machine shop do all the machine work AND order the correct parts to match. Machine shops hate customers brining in their own kits because often the parts are not appropriate, given th emachine work required.
Also, your cylinder head is JUNK!! Do NOT rebuild it. The 2000 and 2001 heads WILL (not might) eventually crack, allowing coolant to get in the oil and /or cylinders. If you remove your head, even if it has not cracked yet, toss it and get a rebuilt 93-99 head.