I'm trying to get a walbro gss340m in my car, the fuel pump is it a resevoir, how do I get the resevoir open to get to the fuel pump without breaking the resevoir?? is there a trick to this?

 

reservoir, you mean platic bucket?
chances are extremely thin that you will get the pump too fit in it correctly
most (other then the racetronix kits) have too just mount it too the arm without the bucket

just take a razor blade and go around the upper part of it scoring the "glue", the lid will pop right off after that