5.7 LS1/T56 swap for 305/5spd '89 C1500

[92 6.0]

I didnt do a manual swap but as for some of your questions:
gauges: Yes get an adapter for the factory oil pressure gauge, and on the coolant temp when I first done my swap I used the 3 wire unit but was told it wasn't as accurate with the obs gauges so I tapped my water pump and put in the factory one for my truck. But my gauge reads the same as the 3 wire unit did.
Pcm: I removed my 92 ecm as its not needed. you only need the one for the ls1.
Radiator: Yes you can use your stock one. I swapped mine to 1 ton rad and installed the 05+ efans.
And the vss in the t56 is the only one you need you dont need the one out of the getrag. as the t56 one is going to be the right one for the pcm.
Hope this makes sense.

[low91]

Unless your on a tight budget I would use these instead of the stock manifolds.LS1 TRUCK - Schoenfeld Headers

I used the three wire sensor and it seemed to read right where it should besides factory gauges aren't that accurate to begin with. If you do use the three wire sensor method you can use the TPS sensor pigtail from your current TBI unit. Also one thing I don't like about the water pump taping method is that what if your water pump goes out and you don't have a way to tap the replacement right away? Gonna be running without knowing how hot your engine is for awhile.

[flattopwill]

Unless your on a tight budget I would use these instead of the stock manifolds.LS1 TRUCK - Schoenfeld Headers

Looks like you got your info straight. The old ecm can come out and go in the trash. I sold mine with the old motor.
For gauges, I recommend tapping the oil cooler block off plate for the oil pressure and using the obs sending unit. Get the coolant temp sensor adapter from S&P and put it in the passenger side head.

[gl18rider]

Thanks for the responses.
I think I'm good with the coolant and oil now.
What about the speedo?