I have a 98 gmc,I removed the 305 vortec, and replaced it with a 350 long block. I put all the 305 sensors, and intake on the new 350 engine. No codes showing on the computer, is there anything that I need to change? The engine is running fairly good. I installed a new transmission at tyhe same time, and there shift light on the inside shows the truck in park when it is in reverse. Is there any way to correct this. Any help will be greatly appreciated.

Thanks,
Sniderman