Is the car burning oil or having any blow by issues? I ask because when you say rebuild it, I'm just wondering if there is a problem or you just think it needs it. If you are not having any oil consumption issues or blowby problems then the bottom end should be fine for a mild build. If you are planning to run a cam such as the M22x from RM or the Skunk2 Pro1 it wouldn't be a bad idea to put in some ARP rod bolts to keep it all together when you're spinning it up high. If you are going to do rod bolts then you may as well do new bearings, pistons, rings and IF the block needs it a slight bore and new hone. If the factory cross hatch is still present then I would just put in new pistons/rings, ACL bearings, ARP rod bolts, and the other obvious stuff,(oil pump, water pump). As far as making power, the previously mentioned cams, Pro1 or m22x would be a great choice for a car that's still a street car. With the Pro 1's and the accompanying Pro series valvetrain, (if you go Pro 1 do not use any other valvetrain other than Pro series from Skunk2) a GOOD header, such as Hytech, RMF, SMSP, Rage, and a way to tune it, if it's obd1 go with crome, even if it's OBD2 get a conversion harness and run crome, it's that good. PR3 pistons or CTR pistons will both net you a higher compression ratio than the ITR pistons but if the head has been milled any you should probably have someone clay the motor to make sure you are not going to have any clearance issues between the valves and the pistons. MR2JZKIDD can get you some good deals on the Skunk2 stuff and most of the other parts you would want and Mainstream is an excellent choice to do your work if you do not intend to do it yourself. So give them a call when you get ready to do anything. Good luck.