there are no rwd autos that are narrow block, they are all wideblocks if i remember correctly. if looking to go turbo just use your stock bottom end, its plenty strong. the stock pistons in the truck are the same as the 1.8l turbocharged cordia/tredia just bigger diameter.

my advice and what i would do if you want to go turbo

use the stock transmission and rear.

new valve stem seals

build a turbo exhaust manifold or source a tredia/cordia unit.

build a speeduino with an adapter to the stock harness.

remove the stock throttle body, replace with 1998 jeep Cherokee 4.0l. (it lines up with the stock one but you need to bore out the bolt holes),(the stock throttle body does not
use a stepper motor, it uses a bidirectional dc motor with a resistor to tell the stock ecm where the throttle plate is, its incompatible with speeduino)

build adapter from the stock idle control motor harness to run the stepper motor on the new throttle plate.

build adapter from stock tps sensor harness to run the jeep tps.

replace stock injectors with 450cc+ injectors.

advance cam timing 5 degrees. (gives more bottom end, the turbo will help it keep breathing on the top.)

OPTIONAL BUT RECOMMENDED https://www.viatrack.ca/

tune

Have fun.



just my 2 cents.