Pre-visualize. Go through the swap in your head and write down all the parts you will need. This helps to eliminate surprises, and will help to cut down on trips to the parts store. Here's a for-instance: When slapping a set of headers onto our HT 383 V-8, we forgot that we needed a set of header bolts. While this might not sound like a big deal, this lapse resulted in another trip to the auto-parts store--a trip we could have avoided if we'd done appropriate planning and thinking.