Treating a race as training.

I guess I need to preface this by saying that I am really a newbie to Tri, I have done one Olympic in 2004 on a summers worth of training with that one race as a goal. Afterwards I promptly gained weight and didnt get back into shape until August 1st of this year when I started working out again. I have spent the last two months building up a base which I hope to work on over the winter and spring with IMKY as a goal for next august. Basically a one year couch to IM. I have found a race that I am interested in coming up that is an end of the regular season 5k/30k/5k Duathlon. I will not have any problems finishing as I have already done the course length in training so far. I am looking to push myself a little even though I am only on two months training, and try and break 1:42 for a pretty hilly bike course. I am wondering if I should try and back off now and do a mini taper before the race or just keep going with my training as planned (this race is kind of a last minute addition)? I have been seeing improvements every week so far so I am assuming that if I treat the race much like a hard training session just with a few easy days friday and sat. I will do fine. The other option, is just to do maintenence rides and runs for the next week and a half to not try and get faster but be well rested. My question is basically if I am seeing improvement gains through continued training should I plan that I will improve before the race, or would being more rested be a better approach?