I can understand wanting to get the bike roadworthy ASAP. I think you should have less issues, since you are using original length tubes and old springs.
I had the slightly shorter tubes, Race Tech valve emulators, brand new springs and new fork oil, so it was sprung for a heavier bike with about an inch of preload -- resulting in an oversprung bike. The ride was too harsh -- not compliant enough when riding on poor road conditions.
When I swapped out the springs, the bike had enough compliance to better deal with potholes and bumps and still track well.
I think that to a degree, by using the old springs the front will have some extra give, but it may be a little bouncy. When you get to rebuilding the front, just call Race Tech and give the the specs of the bike (weight and whether you are running stock vs. shorter tubes). If necessary, they can even do a custom wound spring.
