ABS/TC Lights.... Check the harness going to the hub<s>. The black tubing <not the corregated wire loom> fills up with road silt, and becomes hard as a rock, then the wires inside break. I've had them test good with a DMM and still have both conductors broken internally.
There is so many SC Series 3's in the JY that run fine, I wouldn't dump any money in broken engine parts. I don't know your budget, but I'd start with a running JY motor and do the Exhaust, then Air intake, drop a pulley size, get a tune and call it a day.
I bet the e-brake is totally disconnected, and the cables are just frozen or bolted together.
TransGo shift kit, the accumulator springs and what ever else you can get swapped in from the kit that is easy to get to
