Anything can be done with enough work, but the Colorado 4cyl motors were 2.8 and 2.9 i thought.

 

the last colorado i worked on was a 2.8l. I would say It is not a direct swap.

 

Swap in the I6 from a Colorado, that would be cool.

 

i had a 04 zq8 auto reg cab. I think it had an inline 5 cylinder. It was pretty quick. it would run 10.20s consistantly at the drag strip 1/8 mile completely stock.

 

Oops, I meant I5, not I6.