Since you have the pan already I would try the kit. If you jack up the install you are out nothing to very little since you are already willing to obtain a whole new pan.
If the kit appears to be really cheap or poor in quality, look for a better kit but NAPA usually has good stuff. Just do a little quality assurance on your work and if it doesn't seem up to par, replace it.
I just said the same thing two different ways. Wtfe.