We replaced the timing chain in our 1999 SC2 (twin cam) and were very careful not to move the top or botom sprockets. When we tried to start the car after re-assembly, it tried to start, but would not. I check for spark, it was good. Removed two plugs, very dry, so added some gas directly into the engine, again nothing. Waited 5 minutes tried again, weak sign of firing, but nothing. Seems one of the cams is off, but not sure. I'm very good with small block chevy's and pontiac's, but this is the first real work done on a saturn.

Please advise

 

Small Block Chevy's and Pontiacs when you replace the cam drive belt, the camshaft sits right over the crankshaft in the middle of the engine, it is a simple as aligning the two (generally) spots on the gears and indexing the chain according. Probably learned from reading the instructions and once done almost all V type push rod engines work the same way.
Which leads to the question
did you buy a book of instructions to do this with? You have to align both cams and the crank to index reference points and just taking it apart will cause it to move by itself.
So
having put things like that together wrong even with the instructions and they don't start or run very well when that happens, did you buy the instruction manual?
Cause if you did it is going to be a whole bunch easier to answer your question.

 

Here's a lesson for everyone, I have had a reference book for every car I have owned, except this one. Always get the book! We went last night and bought one, boy do I feel stupid. After working on cars, boats, snowmobiles etc for over 30 years I though I knew how to fix just about anything. WRONG! We are going to tear it back down and hopefully won't have to do a valve job.

 

Don't feel bad, been there done that. Had a Mitsubishi with a timing belt on it. Required to replace it at about 70,000 or so. I put 3 of them on over the years. The third time I got it on wrong.
Yup, stupid wears well I guess.
Have fun.
If you have not heard loud crashing noises, you are probably o.k. usually when things get out of sync, a valve will first go through a piston and then bend.
The big fun alignment project came when I blew a head gasket and had to take the head off.
Boy howdy, a lot of alignment stuff to take into account on a twin overhead cam engine