did you go on dyno or driving and tuning
i tried to find someone to tune mine ire in wisconsin and no shop wants to touch it because law about emissions
if your LC is 1991-1992 your tach wil not work with DD i do not remember exacly why but something with high woltage vs low voltage i have 1991 and i just instaled 1994 tach and it works no problem so you must use 1993 -1994 tack if i remember corectly you do not need to replace whole cluster...
well look at radiator from silverado truck it is almost double the size
i had extreme duty fan clutch and it was keeping the engine cool without a/c on with no problems , but on hwy and a/c on engine temperature will go over 230 F
but i did not like how loud was that fan
so my solution was...
good luck with that fan set up
i bet you they will be blowing constantly
i m using mechanical fan and i ended adding another radiator under the body with two electrical fans to keep it cool in 95 F and up with A/C on
use older style power steering pump and move the engine to driver side and your a/c will fit without any cutting
for oil pan , just use shallow oil pan and no cutting necessary
i used engine from 2007 silverado and did not change anything on it just made two new hose one end to fit toyota steering box and other end to fit gm pump
and also i m using power steering oil cooler from ford F150
for intake pipe i do not remember what size is it but i believe it is 4" one...
i did same thing i swapped to 4.88 before engine swap and just left it in i run 5.3 LS with 4l60 on 35 " tires it runs on higher rpm but you can feel the torque especially off the road and i m leaving it in
i used toyota power wire for ECU also used toyota starter wire to gm starter oil pressure sensor will need to be added to GM oil pan or make adapter to fit it to gm oem spot
temp sensor can be machined to fit in gm hole i m using double sensors gm and toyota if you want cruise you m must...
here you can find all information about wiring with diagrams so you can make your own harness if you have original harness it is pretty easy to put it together all you do is pull extra wires install 4 fuses and all done read the web site you will find all answers also you can use that...
all i did hooked wire from old toyota a/c clutch to gm clutch flushed all R12 stuff and filled the system with r134 Freon and some PAG oil with no problems with idle and inside cab is like fridge when a/c is on
on 1991 land cruiser oil pressure sensor thread is 1/8" BSPT ( BRITISH STANDARD PIPE TAPER ) but i do not know on others , it may be same
if you goo on the bottom and last page 2007 5.3L ls in 1991 80 series you can se how i did some parts for shiftier i used toyota sifter and all other...
yes you cut it down to 12 mm and i used die to cut the tread because my lathe can do only standard thread , but like i said sensor must be OEM there may be other good sensor but i do not know it looks like after market sensors r stamped v.s. OEM solid brass